As filed with the Securities and Exchange Commission on October 10, 2007

Securities Act File No. 333-142625

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

Amendment No. 3
to
FORM S-1

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

ATLAS INDUSTRIES HOLDINGS LLC
(Exact name of Registrant as specified in charter)

One Sound Shore Drive, Suite 302
Greenwich, CT 06830
(203) 983-7933
(Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)

Andrew M. Bursky
Chief Executive Officer
Atlas Industries Holdings LLC
One Sound Shore Drive, Suite 302
Greenwich, CT 06830
(203) 983-7933
(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Approximate date of commencement of proposed sale to the public:
As soon as practicable after the effective date of this registration statement

        If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933 check the following box: o

        If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering: o

        If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering: o

        If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering: o

CALCULATION OF REGISTRATION FEE

(1)

Estimated solely for the purpose of calculating the amount of the registration fee pursuant to Rule 457(o) under the Securities Act of 1933, as amended.

(2)

$6,708 was previously paid.

        The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the Registration Statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

Subject to Completion, dated October 10, 2007

The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

PRELIMINARY PROSPECTUS

13,333,333 Common Shares

        We are making an initial public offering of 13,333,333 common shares representing limited liability company interests in Atlas Industries Holdings LLC, which we refer to as the company.

        Various accredited investors including certain institutions have agreed to purchase, in separate private placement transactions to close in conjunction with the closing of this offering, a number of common shares in the company having an aggregate purchase price of approximately $35.0 million, at a per share price equal to the initial public offering price (which will be approximately 2,333,339 common shares, assuming an initial public offering price per share of $15.00 and that our initial businesses are acquired for the purchase prices disclosed in this prospectus).

        The underwriters have reserved up to 10% of the common shares of this offering for sale pursuant to a directed share program. Currently, no public market exists for our common shares. We expect the initial public offering price to be between $14.00 and $16.00 per share. We have applied to list our common shares on the Nasdaq Global Market under the symbol "AAAA".

        Investing in the common shares involves risks. See the section entitled "Risk Factors" beginning on page 17 of this prospectus for a discussion of the risks and other information that you should consider before making an investment in our securities.

*

Includes the financial advisory fee payable solely to Ferris, Baker Watts, Incorporated of 0.5% of the total offering price.

        The underwriters may also purchase up to an additional 2,000,000 common shares from us at the public offering price, less the underwriting discount and commissions (including the financial advisory fee) within 30 days from the date of this prospectus to cover overallotments.

        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

        We expect to deliver the common shares to the underwriters for delivery to investors on or about            , 2007.

The date of this prospectus is                        , 2007

PROSPECTUS SUMMARY

        This summary highlights selected information appearing elsewhere in this prospectus. For a more complete understanding of this offering, you should read this entire prospectus carefully, including the "Risk Factors" section and the pro forma condensed combined financial statements, the financial statements of our initial businesses and the notes relating thereto and the related "Management's Discussion and Analysis of Financial Condition and Results of Operations" included elsewhere in this prospectus.

        All information and transactions discussed in this prospectus relating to the initial public offering assume an initial public offering of 13,333,333 million of our common shares at $15.00 per share (which is the midpoint of the estimated initial public offering price range set forth on the cover page of this prospectus) and that the initial businesses are acquired for the purchase prices set forth in this prospectus. However, the actual initial public offering size, price per share and purchase prices may be higher or lower than these assumed amounts. In addition, the information and transactions discussed in this prospectus relating to the initial public offering assume that the underwriters have not exercised their overallotment option.

        Certain terms frequently used in this prospectus are discussed in more detail following the section entitled "—Overview of Our Business".

Overview of Our Business

        We have been formed to acquire and manage a group of small to middle market businesses. Through our structure, we offer investors an opportunity to participate in the ownership and growth of a portfolio of businesses that traditionally have been owned and managed by private equity firms, private individuals or families, financial institutions or large conglomerates. The acquisitions of our initial businesses will provide our investors with an immediate opportunity to participate in the ongoing cash flows of a diversified portfolio of businesses through the receipt of regular quarterly distributions. Further, we believe that our management and acquisition strategies will allow us to achieve our goals of growing distributions to our shareholders and increasing shareholder value over time.

        We will seek to acquire controlling interests in small to middle market businesses that operate primarily in commercial and industrial sectors in which members of our management team have historically invested and operated businesses, or in which our management team will develop expertise or experience. In addition, we expect to focus on complex acquisitions in which we believe the value of the underlying business is masked, depressed or not otherwise apparent to other potential buyers due to legal, financial or operational issues. We will also seek to acquire under-managed or under-performing businesses that we believe can be improved under the guidance of our management team and the management teams of the businesses that we own. We expect to improve our businesses over the long term through organic growth opportunities, add-on acquisitions and operational improvements.

        Approximately $233.4 million, comprised of cash and preferred stock of our acquisition subsidiaries, will be used to acquire the equity interests in, and provide debt financing to, the following initial businesses:

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Metal, a manufacturer of highly customized, seamless pressure and mechanical steel tubes for the power generation, oil and natural gas extraction and non-automotive industrial markets;



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Forest, a diversified paper and specialty packaging company serving primarily industrial markets;



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CanAmPac, a manufacturer of paperboard and paperboard packaging used for the packaging of food, beverages and other consumer goods; and



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Pangborn, a designer and marketer of surface preparation equipment and related aftermarket parts and services used in metal manufacturing processes within a diverse range of industries.

        Importantly, we believe that our initial businesses alone will produce sufficient positive cash flows to enable us to make regular quarterly distributions to our shareholders over the long term, regardless of future acquisitions or operational improvements. In addition, immediately following this offering, we anticipate that we will have approximately $100.0 million available for borrowing under our proposed third-party credit facility of $150.0 million and approximately $31.8 million of cash on hand.

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Frequently Used Terms

        Throughout this prospectus we use certain terms repeatedly. To assist you in reading and understanding the disclosure contained in this prospectus, please note the following frequently used terms, which, except as otherwise specified, have the meanings set forth below:

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"Atlas," "we," "us" and "our" refer to the company and our initial businesses together;



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"Metal" refers to Metal Resources LLC and its consolidated subsidiary prior to their acquisition as contemplated herein and refers to Atlas Metal Acquisition Corp. and its consolidated subsidiaries, including Metal Resources LLC, following such acquisition;



•

"Forest" refers to Forest Resources LLC and its consolidated subsidiaries, other than CanAmPac, prior to their acquisition as contemplated herein and refers to Atlas Forest Acquisition Corp. and its consolidated subsidiaries, including Forest Resources LLC, following such acquisition;



•

"CanAmPac" refers to CanAmPac ULC and its consolidated subsidiaries prior to their acquisition as contemplated herein and refers to Atlas CanAmPac Acquisition Corp. and its consolidated subsidiaries, including CanAmPac ULC, following such acquisition;



•

"Pangborn" refers to Capital Equipment Resources LLC and its consolidated subsidiaries prior to their acquisition as contemplated herein and refers to Atlas Pangborn Acquisition Corp. and its consolidated subsidiaries, including Capital Equipment Resources LLC, following such acquisition;



•

"acquisition subsidiaries" refers, collectively, to Atlas Metal Acquisition Corp., Atlas Forest Acquisition Corp., Atlas CanAmPac Acquisition Corp. and Atlas Pangborn Acquisition Corp.;



•

"our initial businesses" refers, collectively, to Metal, Forest, CanAmPac and Pangborn;



•

"our businesses" refers, collectively, to the businesses in which we may own a controlling interest from time to time; and



•

"our shareholders" refers to holders of our common shares.

Our Manager

        The company will engage Atlas Industries Management LLC, which we refer to as our manager, to manage the day-to-day operations and affairs of the company, oversee the management and operations of our businesses and perform certain other services on our behalf, subject to the oversight of our board of directors. We believe our manager's expertise and experience will be a critical factor in executing our strategy to meet the goals of growing distributions to our shareholders and increasing shareholder value. Effective January 1, 2008, all of the employees of Atlas FRM LLC (d/b/a Atlas Holdings LLC), which we refer to as Atlas Holdings, will become employees of our manager. Andrew M. Bursky, our Chief Executive Officer, and Timothy J. Fazio, our President, are the managing members of our manager and, as a result, our manager is and will be an affiliate of Messrs. Bursky and Fazio and the other entities controlled by Messrs. Bursky and Fazio, including Atlas Holdings. We refer to Messrs. Bursky and Fazio together with their affiliated entities, including our manager, as the AH Group.

        Initially, our manager will employ or engage eight experienced professionals, whom we refer to collectively as our management team. The senior members of our management team are Andrew M. Bursky, Timothy J. Fazio, David I. J. Wang, Daniel E. Cromie, Edward J. Fletcher and Philip E. Schuch. A majority of the senior members of our management team have worked together for over seven years, and some have worked together for over 14 years. The senior members of our management team, their affiliates and certain members of our board of directors, through Atlas Titan Management Investments LLC, which we refer to as AT Management, have agreed to purchase approximately $14.7 million of common shares in a separate private placement transaction to close in conjunction with this offering at a per share price equal to the initial public offering price. See the

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section entitled "Our Manager" for more information about our manager, our management team and our relationship with our manager and our management team.

        Since 2002, our management team has developed and grown multiple sector-specific platform businesses, through the consummation of 11 acquisitions. The revenue of the platform businesses grown and developed by our management team grew, due to a combination of acquisitions, organic growth and operational improvements, from approximately $45.4 million for the year ended December 31, 2002 to approximately $588.7 million for the year ended December 31, 2006. During the six months ended June 30, 2007, our management team completed another acquisition of a business with revenues of approximately $250.2 million for the year ended December 31, 2006. Collectively, our management team has approximately 100 years of combined experience in acquiring and managing small and middle market businesses and has overseen the acquisitions of over 100 businesses.

        The company and our manager will enter into a management services agreement pursuant to which we will pay our manager a quarterly management fee equal to 0.5% (2.0% annualized) of the company's adjusted net assets for services performed. The management fee will be subject to offset pursuant to fees paid to our manager by our businesses under separate management services agreements that our manager will enter into with our initial businesses, which we refer to as offsetting management services agreements. In addition, a portion of the management fee will be paid in the form of common shares for the first eight quarterly payments, which will have the effect of enhancing our liquidity. See the sections entitled "Management Services Agreement" and "Our Manager—Our Relationship with Our Manager—Our Manager as a Service Provider" for more information about the terms of the management services agreement and the calculation of the management fee, respectively.

        Our Chief Executive Officer, President, Chief Financial Officer and Chief Accounting Officer will be employees of our manager and will be seconded to the company, which means that these employees will be assigned by our manager to work for the company during the term of the management services agreement. Although these executive officers will be employees of our manager, they will report directly to our board of directors.

        The company will not reimburse our manager for any of our manager's overhead expenses related to the services performed by our manager pursuant to the management services agreement, including the compensation of our executive officers and other seconded personnel providing services to us, which are encompassed by the management fee. However, pursuant to the management services agreement, our manager has the right to seek reimbursement relating to compensation paid to the Chief Financial Officer and seconded personnel serving on the staff of the Chief Financial Officer, including the Chief Accounting Officer; however, our manager currently does not intend to seek any reimbursement relating to our Chief Financial Officer and Chief Accounting Officer.

        Our manager will bear all expenses incurred, which can be significant, in the identification, evaluation, management, performance of due diligence on, negotiation and oversight of a potential acquisition if our board of directors does not resolve to pursue such acquisition. These expenses may also include expenses related to travel, marketing and attendance at industry events and the retention of outside service providers. However, the company generally will otherwise be responsible for paying costs and expenses relating to its business and operations, including all costs and expenses incurred by our manager or its affiliates on behalf of the company during the term of the management services agreement. The compensation committee of our board of directors will review, on an annual basis, all costs and expenses reimbursed to our manager. See the sections entitled "Management—Executive Officers of the Company" and "Management Services Agreement" for more information about the secondment of our executive officers and "Our Manager—Our Relationship with Our Manager—Our Manager as a Service Provider—Reimbursement of Expenses" for more information about the reimbursement of expenses to our manager.

        Our manager owns 100% of the allocation shares of the company, which are a separate class of limited liability company interests that, together with the common shares, will comprise all of the

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classes of equity interests of the company. Our manager received the allocation shares with its initial capitalization of the company. The allocation shares generally will entitle our manager to receive a 20% profit allocation as a form of incentive designed to align the interests of our manager with those of our shareholders. Profit allocation has two components: an equity-based component and a distribution-based component. The equity-based component will be paid when the market for our shares appreciates, subject to certain conditions and adjustments. The distribution-based component will be paid when the distributions we pay to our shareholders exceed an annual hurdle rate of 8.0%, subject to certain conditions and adjustments. While the equity-based component and distribution-based component are interrelated in certain respects, each component may independently result in a payment of profit allocation if the relevant conditions to payment are satisfied. There will be no payments of profit allocation prior to December 31, 2010. Our board of directors has the right to elect to make any payment of profit allocation in the form of securities of the company. See the section entitled "Our Manager—Our Relationship with Our Manager—Our Manager as an Equity Holder—Manager's Profit Allocation" for more information about the calculation and payment of profit allocation.

        In addition, we intend to enter into a supplemental put agreement with our manager pursuant to which our manager will have the right, subject to certain conditions, to cause the company to purchase the allocation shares then owned by our manager following the termination of the management services agreement for a price to be determined in accordance with the supplemental put agreement, which we refer to as the put price. See the section entitled "Our Manager—Our Relationship with Our Manager—Our Manager as an Equity Holder—Supplemental Put Agreement" for more information about the supplemental put agreement.

        In general, the management fee, put price and profit allocation will be, or will create, payment obligations of the company and, as a result, will be senior in right to the payment of distributions to our shareholders.

Our Strategy

        Our goals are to grow distributions to our shareholders and to increase shareholder value over the long term. We intend to do this by focusing on increasing the cash flows of our businesses as well as seeking to acquire and manage other small to middle market businesses. We believe we can increase the cash flows of our businesses by applying our intellectual capital to continually improve and grow our businesses.

Management Strategy

        Our management strategy is to operate our businesses in a manner that leverages our "intellectual capital"—the knowledge base built upon the combined years of operating experience, expertise and strategic relationships developed by our management team.

        In executing our management strategy, our manager intends to work with operating advisors, whom we refer to as our manager's operating partners, who are seasoned managers of operating companies in business sectors in which we have focused or intend to focus in the future. Our manager's operating partners provide our manager and our businesses with additional intellectual capital, independent technical assistance and advice with respect to acquiring and operating businesses in particular sectors on a level that is not otherwise achievable without expending significant time and expense. See the section entitled "Our Manager—Operating Partners" for more information about our manager's operating partners.

        Our management strategy of applying our intellectual capital to our businesses provides us with certain advantages, including the ability to:

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identify, analyze and pursue prudent organic growth strategies, including selective capital investments to increase capacity or reduce operating costs;



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identify attractive external growth and acquisition opportunities;

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identify and execute operational improvements and integration opportunities that will lead to lower operating costs and operational optimization;



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instill financial discipline by monitoring financial and operational performance from an operator's perspective;



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implement structured incentive compensation programs, including management equity ownership, tailored to each of our businesses to attract and retain talented personnel; and



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provide the management teams of our businesses the opportunity to leverage our experience and expertise to develop and implement business and operational strategies.

        We also believe that our long-term perspective provides us with certain additional advantages, including the ability to:

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recruit and develop talented management teams for our businesses that are familiar with the industries in which our businesses operate and will generally seek to manage and operate our businesses with a long-term focus, rather than a short-term investment objective;



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focus on developing and implementing business and operational strategies to build and sustain shareholder value over the long term;



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create sector-specific platform businesses enabling us to take advantage of vertical and horizontal acquisition opportunities within a given sector;



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achieve exposure in certain industries in order to create opportunities for future acquisitions; and



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develop and maintain long-term collaborative relationships with customers and suppliers.

        We intend to continually increase our intellectual capital as we operate our businesses and acquire new businesses and as our manager identifies and recruits qualified operating partners and managers for our businesses.

Acquisition Strategy

        Our acquisition strategy is to identify attractive horizontal and vertical small and middle market acquisition opportunities with purchase prices between $20 million and $100 million in the industry sectors in which we own businesses or in which we have or will develop intellectual capital. In particular, we intend to pursue complex transactions where, we believe, the value of the underlying businesses is masked, depressed or not otherwise apparent to other potential buyers due to legal, financial or operational issues. In addition, we intend to pursue acquisitions of under-managed or under-performing businesses that, we believe, can be improved pursuant to our management strategy. We believe that our intellectual capital offers us an advantage in identifying opportunities and acquiring target businesses at attractive prices and on favorable terms.

        We believe that the merger and acquisition market for small to middle market businesses is highly fragmented and provides opportunities to purchase businesses at attractive prices relative to larger market transactions. For example, according to Mergerstat, during the twelve-month period ended September 30, 2007, businesses that sold for less than $100 million were sold for a median of approximately 7.9x the trailing twelve months of earnings before interest, taxes, depreciation and amortization as compared to a median of approximately 9.9x for businesses that sold for between $100 million and $300 million and 12.3x for businesses that sold for over $300 million. In addition, we believe that our management team's understanding of the merger and acquisition market for small to middle market businesses facing legal, financial or operational issues provides us with certain competitive advantages.

        Our acquisition strategy is predicated on the following guiding principles:

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investing primarily in business sectors and industries in which we have, or will develop, operating experience or expertise;

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seeking opportunities in sectors and industries where entrepreneurial businesses with capable management teams, acting under the guidance and support of our management team and our manager's operating partners, can achieve attractive financial results;



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acquiring under-managed and under-performing businesses where implementation and application of our management strategy can improve financial and operational performance;



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pursuing complex transactions where value is masked, depressed or not otherwise apparent to other potential buyers due to legal, financial or operational issues; and



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acquiring and integrating businesses that are complementary to our businesses or the products that our businesses produce and sell.

        We expect the process of acquiring new businesses to be time-consuming and complex. Our management team has historically taken from 3 to 18 months to perform due diligence on, negotiate and close acquisitions. We intend to raise capital for additional acquisitions primarily through debt financing at the company level such as our proposed third-party credit facility, additional equity offerings, the sale of all or a part of our businesses or by undertaking a combination of any of the above.

Overview of this Offering and the Related Transactions

This Offering and the Private Placements

        We are making an initial public offering of 13,333,333 common shares and expect to receive net proceeds of approximately $186.0 million. In addition, upon closing the initial public offering, we will sell 2,333,339 common shares for approximately $35.0 million in connection with private placement transactions. Specifically, Atlas Titan Investments LLC, which we refer to as AT Investments, and AT Management have each agreed to purchase approximately $15.0 million and $14.7 million of our common shares, respectively, at a per share price equal to the initial public offering price, pursuant to private placement transactions to close in conjunction with the closing of this offering. Further, each of Allstate Life Insurance Company, Hancock Mezzanine Partners III, L.P., John Hancock Life Insurance Company and John Hancock Variable Life Insurance Company have collectively agreed to purchase an aggregate of $5.3 million of our common shares, at a per share price equal to the initial public offering price, pursuant to private placement transactions to close in conjunction with the closing of this offering. We refer to these institutional investors together with AT Management and AT Investments as the private placement participants.

External and Internal Debt Financings

        We intend to enter into a third-party credit facility allowing for the borrowing of up to $150.0 million of which we intend to draw approximately $50.0 million in conjunction with the closing of this offering.

        We also intend to enter into the following internal credit facilities with our acquisition subsidiaries, which will, in turn, make loans to our initial businesses as follows:

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We intend to provide Atlas Metal Acquisition Corp. with term loans of approximately $56.0 million and a $20.0 million financing commitment pursuant to a revolving credit facility. The full amount of the term loans and approximately $350,000 of the revolving loan commitment, totaling approximately $56.4 million, will be funded in conjunction with the closing of this offering. Atlas Metal Acquisition Corp. will loan approximately $56.0 million to Metal in conjunction with the closing of this offering.



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We intend to provide Atlas Forest Acquisition Corp. with term loans of approximately $46.5 million and a $21.0 million financing commitment pursuant to a revolving credit facility. The full amount of the term loans and approximately $1.0 million of the revolving loan commitment, totaling approximately $47.5 million, will be funded in conjunction with the closing

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of this offering. Atlas Forest Acquisition Corp. will loan approximately $46.5 million to Forest in conjunction with the closing of this offering.

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We intend to provide Atlas CanAmPac Acquisition Corp. with term loans of approximately $35.0 million and a $16.5 million financing commitment pursuant to a revolving credit facility. The full amount of the term loans and approximately $763,000 of the revolving loan commitment, totaling approximately $35.8 million, will be funded in conjunction with the closing of this offering. Atlas CanAmPac Acquisition Corp. will loan approximately $35.0 million to CanAmPac in conjunction with the closing of this offering.



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We intend to provide Atlas Pangborn Acquisition Corp. with terms loans of approximately $13.0 million and a $5.0 million financing commitment pursuant to a revolving credit facility. The full amount of the term loans and approximately $294,000 of the revolving loan commitment, totaling approximately $13.3 million, will be funded in conjunction with the closing of this offering. Atlas Pangborn Acquisition Corp. will loan approximately $13.0 million to Pangborn in conjunction with the closing of this offering.

Acquisition of Our Initial Businesses

        We will use approximately $230.6 million of the net proceeds from this offering, the private placement transactions and the initial borrowing under our third-party credit facility to capitalize and make the loans described above to our acquisition subsidiaries. Our acquisition subsidiaries will use these proceeds, together with $2.8 million of preferred stock, to acquire and make the loans described above to our initial businesses as follows:

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Atlas Metal Acquisition Corp. will use approximately $81.9 million of cash and $900,000 of preferred stock to make the above described loans and acquire Metal from a group of private investors, including affiliates of our manager that are controlled by Messrs. Bursky and Fazio, certain

members of management of Metal and Forest and certain members of the company's board of directors. We refer to this group of sellers as the Metal selling group.

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Atlas Forest Acquisition Corp. will use approximately $70.0 million of cash and $1.0 million of preferred stock to make the above described loans and acquire Forest from a group of private investors, including affiliates of our manager that are controlled by Messrs. Bursky and Fazio, certain members of management of Forest and the subsidiaries of Forest, certain members of the company's board of directors and certain other private investors in Forest. We refer to this group of sellers as the Forest selling group.



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Atlas CanAmPac Acquisition Corp. will use approximately $58.7 million of cash and $600,000 of preferred stock to make the above described loans and acquire CanAmPac from Forest and an institutional investor unaffiliated with our manager and any other selling group. We refer to this group of sellers as the CanAmPac selling group. While CanAmPac is a subsidiary of Forest, the two businesses are currently operated and managed, and following such acquisition will continue to be operated and managed, separately as two distinct entities. As a result, the company intends to acquire these two businesses in two separate acquisitions so as to give effect to the method by which the company intends to operate and manage these businesses following such acquisitions.



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Atlas Pangborn Acquisition Corp. will use approximately $20.0 million of cash and $300,000 of preferred stock to make the above described loans and acquire Pangborn from a group of private investors, including affiliates of our manager that are controlled by Messrs. Bursky and Fazio, certain members of management of Pangborn, Forest, the subsidiaries of Forest and Metal, certain members of the company's board of directors and certain other private investors in Pangborn. We refer to this group of sellers as the Pangborn selling group, and we refer to all of the above-described selling groups collectively as the selling groups.

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See the section entitled "Principal Shareholders/Share Ownership of Directors and Executive Officers—Our Initial Businesses" for more information about the interests in our initial businesses that we will acquire from our directors and executive officers.

Transactions with Related Parties

        Upon consummation of the acquisitions of our initial businesses, the selling groups will receive approximately $126.1 million, comprised of $123.3 million in cash and $2.8 million of preferred stock of our acquisition subsidiaries. Members of the AH Group will receive approximately $33.9 million in connection with the sale of their interests in our initial businesses. Our management team (other than members of the AH Group) will receive approximately $5.9 million in connection with the sale of their interests in our initial businesses. Our directors (other than members of the AH Group and our management team) will receive approximately $1.5 million in connection with the sale of their interests in our initial businesses. The officers and directors of our initial businesses (who are not encompassed by any of the foregoing categories) will receive approximately $50.2 million in connection with the sale of their interests in our initial businesses.

Summary of Our Initial Businesses

        A summary of our initial businesses is as follows:

Metal

        Metal, headquartered in South Lyon, Michigan, manufactures highly customized, precision-tolerance cold drawn seamless pressure and mechanical steel tubes in a wide range of alloy and carbon grades. Metal's products are used for niche applications in the power generation, oil and natural gas extraction and non-automotive industrial markets. Metal sells its products to an account base of over 600 customers around the world.

Forest

        Forest, headquartered in Bridgeview, Illinois, is a producer of recycled paper and specialty packaging products. Forest operates from 10 manufacturing facilities located throughout North America, including seven packaging plants in Illinois, California, Pennsylvania, Missouri, Georgia, Ontario and Quebec and three paper mills located in Indiana and Illinois. Forest serves approximately 2,500 customers who operate in diverse industrial and consumer markets on a local, regional and national basis in North America.

CanAmPac

        CanAmPac, headquartered in Toronto, Ontario, operates from two facilities in Ontario and is an integrated manufacturer of recycled paperboard and paperboard packaging used in the consumer packaged goods industry. CanAmPac paperboard products package a wide range of consumer items including frozen and dry foods, beverages, pet products, diverse household products and hardware. CanAmPac has over 250 customers including many of the leading consumer packaged goods manufacturers in the world.

Pangborn

        Pangborn, headquartered in Hagerstown, Maryland, designs and markets surface preparation equipment and related aftermarket parts and services used in metal manufacturing processes within a diverse range of industries. The equipment and aftermarket parts Pangborn produces are used in shot-blasting, a process by which the surfaces of targeted objects are cleaned through the controlled propulsion of shot or other abrasive particles at such objects. Pangborn has been in operation for over 100 years serving customers in the automotive, building and infrastructure, heavy duty trucking,

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national defense, construction, petroleum and aerospace industries. Pangborn has approximately 1,500 customers in these and other markets and has sold its products throughout the world.

Corporate Structure

        The company is a recently formed Delaware limited liability company. Your rights as a holder of common shares, and the fiduciary duties of our board of directors and executive officers, and any limitations relating thereto, are set forth in the operating agreement governing the company, which we refer to as the LLC agreement, and may differ from those applying to a Delaware corporation. However, subject to certain exceptions, the documents governing the company specify that the duties of its directors and officers will be generally consistent with the duties of directors and officers of a Delaware corporation. See the section entitled "Description of Shares" for more information about the LLC agreement.

        In addition, investors in this offering will be shareholders in the company, which is a limited liability company, and, as such, will be subject to tax under partnership income tax provisions. Under the partnership income tax provisions, the company will not incur any U.S. federal income tax liability; rather, each of our shareholders will be required to take into account his or her allocable share of company income, gain, loss, and deduction. As a holder of common shares, you may not receive cash distributions sufficient in amount to cover taxes in respect of your allocable share of the company's net taxable income. The company will file a partnership return with the Internal Revenue Service, or IRS, and will issue tax information, including a Schedule K-1, to you that describes your allocable share of the company's income, gain, loss, deduction, and other items. The U.S. federal income tax rules that apply to partnerships are complex, and complying with the reporting requirements may require significant time and expense. See the section entitled "Material U.S. Federal Income Tax Considerations" for more information.

        The company will have two classes of limited liability company interests following this offering - the common shares, which are being offered in this offering, and the allocation shares, all of which have been and will continue to be held by our manager. See the section entitled "Description of Shares" for more information about the common shares and the allocation shares.

        Our board of directors will oversee the management of the company, our businesses and the performance of our manager. Initially, our board of directors will be comprised of eight directors, all of whom have been appointed by our manager, as holder of the allocation shares, and at least five of whom are independent directors. Following this initial appointment, six of the directors will be elected by our shareholders.

        As holder of the allocation shares, our manager will have the continuing right to appoint two directors to our board of directors, subject to adjustment. Appointed directors will not be required to stand for election by our shareholders. See the section entitled "Description of Shares—Voting and Consent Rights—Appointed Directors" for more information about our manager's right to appoint a director.

Corporate Information

        Our principal executive offices are located at One Sound Shore Drive, Suite 302, Greenwich, Connecticut 06830, and our telephone number is 203-983-7933. We have applied to list the common shares on the Nasdaq Global Market under the symbol "AAAA". The company's website is located at www.AtlasLLC.com.

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Our Proposed Organizational Structure⁽¹⁾

(1)

All percentages are approximate and assume that we sell all of the common shares offered in this offering and the separate private placement transactions and that the underwriters do not exercise their overallotment option. The supplemental put agreement, offsetting management services agreements, transaction services agreements, our proposed third-party credit facility and the inter-company loans and certain other elements of the transactions are not shown. You should read this entire prospectus for a complete understanding of all the transactions being undertaken, including their participants, in connection with this offering.

(2)

See the sections entitled "—Overview of this Offering and the Related Transactions" and "Certain Relationships and Related Persons Transactions" for further information regarding the private placement transactions.

(3)

The allocation shares, which carry the right to receive a profit allocation, will represent less than a 0.1% equity interest in the company upon closing of this offering assuming that we sell all of the common shares offered in this offering and the separate private placement transactions.

(4)

Includes Messrs. Bursky and Fazio who serve as its managing members and Atlas Titan Carry I LLC and Atlas Titan Carry II LLC as its limited members. Messrs. Bursky and Fazio are the managing members of Atlas Titan Carry I LLC and TRAL Carry LLC is its limited member. Messrs. Bursky and Fazio are the non-economic managing members of Atlas Titan Carry II LLC and certain members of our management team are its limited members.

(5)

Acquired through our subsidiary, Atlas Metal Acquisition Corp.

(6)

Acquired through our subsidiary, Atlas Forest Acquisition Corp.

(7)

Acquired through our subsidiary, Atlas CanAmPac Acquisition Corp.

(8)

Acquired through our subsidiary, Atlas Pangborn Acquisition Corp.

(9)

Other than the preferred stock issued in connection with the acquisition of each initial business, all other equity interests of our acquisition subsidiaries will be owned by the company.

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The Offering

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        The above discussion assumes that the underwriters' overallotment option is not exercised. If the overallotment option is exercised in full, we will issue and sell an additional 2,000,000 common shares to the public.

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SUMMARY FINANCIAL DATA

        The company was formed on December 26, 2006 and has conducted no operations and has generated no revenues to date. We will use the net proceeds from this offering, the separate private placement transactions and the initial borrowing under our proposed third-party credit facility to acquire and make loans to our initial businesses.

        The following summary financial data presents the historical financial information for Metal, Forest, CanAmPac and Pangborn and does not reflect the accounting for these businesses upon completion of the acquisitions and the operation of the businesses as a consolidated entity. This historical financial data does not reflect the recapitalization of these businesses upon acquisition by the company. As a result, this historical data may not be indicative of the future performance of these businesses following their acquisition by the company and recapitalization. You should read this information in conjunction with the sections entitled "Selected Financial Data" and "Management's Discussion and Analysis of Financial Condition and Results of Operations", the financial statements and notes thereto, and the pro forma condensed combined financial statements and notes thereto which reflect the completion of the acquisitions and related transactions thereto, all included elsewhere in this prospectus.

        The summary financial data for Metal for the years ended December 31, 2005 and 2006 were derived from Metal's audited consolidated financial statements included elsewhere within this prospectus. The summary financial data for Metal for the six month periods ended June 30, 2006 and 2007 were derived from Metal's unaudited condensed interim financial statements included elsewhere within this prospectus.

        The summary financial data for Forest for the year ended December 31, 2005 was derived from Forest's audited consolidated financial statements included elsewhere in this prospectus. The summary financial data for Forest at December 31, 2006 and for the year ended December 31, 2006 were derived from "Note 21—Consolidating Balance Sheet and Statement of Operations", which we refer to as Note 21, to the audited financial statements of Forest, excluding all financial data related to CanAmPac as of the date and for the periods indicated therein, included elsewhere in this prospectus. The summary financial data for Forest for the six month periods ended June 30, 2006 and 2007 were derived from "Note 14—Consolidating Balance Sheet and Statement of Operations", which we refer to as Note 14, to Forest's unaudited condensed interim financial statements included elsewhere within this prospectus.

        The summary financial data for CanAmPac for the year ended December 31, 2005 (predecessor) and the four month period ended April 30, 2006 (predecessor) were derived from Roman's Paperboard and Packaging's audited carve-out financial statements (predecessor) included elsewhere in this prospectus. The summary financial data for CanAmPac for the eight month period ended December 31, 2006 (successor) and at December 31, 2006 (successor) were derived from Note 21 to the audited financial statements of Forest, including only financial data related to CanAmPac as of the date and for the periods indicated therein, included elsewhere in this prospectus. The summary financial data for CanAmPac for the period May 1, 2006 through June 30, 2006 (successor) and the six month period ended June 30, 2007 (successor) were derived from Note 14 to Forest's unaudited condensed interim financial statements included elsewhere in this prospectus, including only the financial data related to CanAmPac as of the date and periods indicated therein. The balances presented for the year ended December 31, 2005 and for the four month period ended April 30, 2006 were converted to U.S. dollars for the convenience of the reader at a conversion rate of one Canadian dollar to $0.87 (actual) U.S. dollar, which approximates the mean exchange rate in effect during 2006. The balances presented for both the period May 1, 2006 through June 30, 2006 (successor) and the six month period ended June 30, 2007 (successor) were converted to U.S. dollars at a conversion rate of one Canadian dollar to $0.88 (actual) U.S. dollar.

        The summary financial data for Pangborn for the year ended December 31, 2005 (predecessor), for the period January 1, 2006 to June 4, 2006 (predecessor), for the period June 5, 2006 to December 31, 2006 (successor) and at December 31, 2006 (successor) were derived from Pangborn's audited consolidated financial statements included elsewhere in this prospectus. The summary financial data for Pangborn for the period June 5, 2006 through June 30, 2006 and the six month period ended June 30, 2007 were derived from Pangborn's unaudited condensed interim financial statements included elsewhere within this prospectus.

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Metal

Forest

CanAmPac

15

Pangborn

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RISK FACTORS

        An investment in our common shares involves a high degree of risk. You should carefully read and consider all of the risks described below, together with all of the other information contained or referred to in this prospectus, before making an investment decision with respect to our common shares or the company. If any of the following events occur, our financial condition, business and results of operations (including cash flows) may be materially adversely affected. In that event, the market price of our common shares could decline, and you could lose all or part of your investment.

Risks Related to Our Business and Structure

We are a new company with no history and we may not be able to manage our initial businesses on a profitable basis.

        We were formed on December 26, 2006 and have conducted no operations and have generated no revenues to date. We will use the net proceeds from this offering, the separate private placement transactions and the initial borrowing under our third-party credit facility, to acquire the equity interests in and make loans to our initial businesses. Our manager will manage the day-to-day operations and affairs of the company and oversee the management and operations of our initial businesses, subject to the oversight of our board of directors. Our management team has collectively approximately 100 years of experience in acquiring and managing small and middle market businesses. However, if we do not develop effective systems and procedures, including accounting and financial reporting systems, to manage our operations as a consolidated public company, we may not be able to manage the combined enterprise on a profitable basis, which could adversely affect our ability to pay distributions to our shareholders. In addition, the pro forma condensed combined financial statements of our initial businesses cover periods during which some of our initial businesses were not under common control or management and, therefore, may not be indicative of our future financial condition, business and results of operations.

Our audited financial statements will not include meaningful comparisons to prior years until the end of our 2009 fiscal year and may differ substantially from the pro forma condensed combined financial statements included in this prospectus.

        Our audited financial statements will include consolidated results of operations and cash flows only for the period from the date of the acquisition of our initial businesses to year-end. Because we will purchase our initial businesses only after the closing of this offering and recapitalize each of them, we anticipate that our audited financial statements will not contain full-year consolidated results of operations and cash flows until the end of our 2008 fiscal year, which may differ substantially from the pro forma combined financial statements included in this prospectus. Consequently, meaningful year-to-year comparisons will not be available, at the earliest, until two fiscal years following the completion of this offering.

Our future success is dependent on the employees of our manager, our manager's operating partners and the management teams of our businesses, the loss of any of whom could materially adversely affect our financial condition, business and results of operations.

        Our future success depends, to a significant extent, on the continued services of the employees of our manager, most of whom have worked together for a number of years. Because certain employees of our manager were involved in the acquisitions of these initial businesses while working for Atlas Holdings and, since such acquisitions, have overseen the operations of these businesses, the loss of their services may materially adversely affect our ability to manage the operations of our initial businesses. While our manager may have employment agreements with certain of its employees, these employment agreements may not prevent our manager's employees from leaving our manager or from competing with us in the future. In addition, we will depend on the assistance provided by our manager's operating partners in

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evaluating, performing diligence on and managing our businesses. The loss of any employees of our manager or any of our manager's operating partners may materially adversely affect our ability to implement or maintain our management strategy or our acquisition strategy.

        The future success of our businesses also depends on their respective management teams because we intend to operate our businesses on a stand-alone basis, primarily relying on their existing management teams for management of our businesses' day-to-day operations. Consequently, their operational success, as well as the success of any organic growth strategy, will be dependent on the continuing efforts of the management teams of our businesses. We will seek to provide these individuals with equity incentives in the company and to have employment agreements with certain persons we have identified as key to their businesses. However, these measures may not prevent these individuals from leaving their employment. The loss of services of one or more of these individuals may materially adversely affect our financial condition, business and results of operations.

We may experience difficulty as we evaluate, acquire and integrate additional businesses, which could result in drains on our resources, including the attention of our management, and disruptions of our on-going business.

        A component of our strategy is to acquire additional businesses. We will focus on small to middle market businesses in various industries. Generally, becau