Director and Officer Lock-Up Agreement

Exhibit 6

Director and Officer Lock-Up Agreement

December 13, 2010

Xxxxxxx Lynch, Pierce, Xxxxxx & Xxxxx Incorporated

Xxx Xxxxxx Xxxx

Xxx Xxxx, Xxx Xxxx 00000

Ladies and Gentlemen:

This Lock-Up Agreement is being delivered to you in connection with the proposed Underwriting Agreement (the “Underwriting Agreement”) to be entered into by International Coal Group, Inc., a Delaware corporation (the “Company”), the Selling Stockholders named therein and you and the other Underwriters named in Schedule A to the Underwriting Agreement, with respect to the public offering (the “Offering”) of common stock, par value $0.01 per share, of the Company (the “Common Stock”). Capitalized terms used herein without definition shall have the respective meanings ascribed to them in the Underwriting Agreement.

In order to induce you to enter into the Underwriting Agreement, the undersigned agrees that, for a period (the “Lock-Up Period”) beginning on the date hereof and ending on, and including, the date that is 90 days after the date of the final prospectus supplement relating to the Offering, the undersigned will not, without the prior written consent of Xxxxxxx Lynch, Pierce, Xxxxxx & Xxxxx Incorporated, (i) sell, offer to sell, contract or agree to sell, hypothecate, pledge, grant any option to purchase or otherwise dispose of or agree to dispose of, directly or indirectly, or file (or participate in the filing of) a registration statement with the Securities and Exchange Commission (the “Commission”) in respect of, or establish or increase a put equivalent position or liquidate or decrease a call equivalent position within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission promulgated thereunder (the “Exchange Act”) with respect to, any Common Stock or any other securities of the Company that are substantially similar to Common Stock, or any securities convertible into or exchangeable or exercisable for, or any warrants or other rights to purchase, the foregoing, (ii) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of Common Stock or any other securities of the Company that are substantially similar to Common Stock, or any securities convertible into or exchangeable or exercisable for, or any warrants or other rights to purchase, the foregoing, whether any such transaction is to be settled by delivery of Common Stock or such other securities, in cash or otherwise or (iii) publicly announce an intention to effect any transaction specified in clause (i) or (ii). The foregoing sentence shall not apply to (a) the sale of Firm Shares or Additional Shares by any Selling Stockholder to the Underwriters pursuant to the Underwriting Agreement, (b) bona fide gifts, provided the recipient thereof agrees in writing with the Underwriters to be bound by the terms of this Lock-Up Agreement, (c) dispositions to any trust for the direct or indirect benefit of the undersigned and/or the immediate family of the undersigned, provided that such trust agrees in writing with the Underwriters to be bound by the terms of this Lock-Up Agreement, (d) transfers occurring by operation of law, such as rules of

descent and distribution, or statutes governing the effects of a merger or a qualified domestic order, provided that the transferee agrees in writing with the Underwriters to be bound by the terms of this Lock-Up Agreement and (e) transfers by the undersigned, if a limited partnership, limited liability company or corporation, to any limited or general partner, member or corporate subsidiary, as the case may be, of the undersigned, provided that the recipient thereof agrees in writing to be bound by the terms of this Lock-Up Agreement; provided that any such transfer pursuant to clauses (b), (c), (d) and (e) shall not involve a disposition for value. For purposes of this paragraph, “immediate family” shall mean the undersigned and the spouse, any lineal descendent, father, mother, brother or sister of the undersigned.

In addition, the undersigned hereby waives any rights the undersigned may have to require registration of Common Stock in connection with the filing of any registration statement relating to the Offering. The undersigned further agrees that, for the Lock-Up Period, the undersigned will not, without the prior written consent of the Xxxxxxx Lynch, Pierce, Xxxxxx & Xxxxx Incorporated, make any demand for, or exercise any right with respect to, the registration of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock, or warrants or other rights to purchase Common Stock or any such securities.

Notwithstanding the above, if (a) during the period that begins on the date that is fifteen (15) calendar days plus three (3) business days before the last day of the Lock-Up Period and ends on the last day of the Lock-Up Period, the Company issues an earnings release or material news or a material event relating to the Company occurs; or (b) prior to the expiration of the Lock-Up Period, the Company announces that it will release earnings results during the sixteen (16) day period beginning on the last day of the Lock-Up Period, then the restrictions imposed by this Lock-Up Agreement shall continue to apply until the expiration of the date that is fifteen (15) calendar days plus three (3) business days after the date on which the issuance of the earnings release or the material news or material event occurs; provided, that this sentence shall not apply if (i) the safe harbor provided by Rule 139 under the Act is available in the manner contemplated by Conduct Rule 2711(f)(4) of FINRA; and (ii) within the 3 business days preceding the 15th calendar day before the last day of the Lock-Up Period, the Company delivers (in accordance with Section 14 of the Underwriting Agreement) to Xxxxxxx Lynch, Pierce, Xxxxxx & Xxxxx Incorporated a certificate, signed by the Chief Financial Officer or Chief Executive Officer of the Company, certifying on behalf of the Company that the Company’s shares of Common Stock are “actively traded securities,” within the meaning of Conduct Rule 2711(f)(4) of FINRA.

The undersigned hereby confirms that the undersigned has not, directly or indirectly, taken, and hereby covenants that the undersigned will not, directly or indirectly, take, any action designed, or which has constituted or will constitute or might reasonably be expected to cause or result in the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the shares of Common Stock.

The undersigned hereby authorizes the Company and its transfer agent, during the Lock-Up Period, to decline the transfer of or to note stop transfer restrictions on the stock register and other records relating to shares of Common Stock or other securities subject to this

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Lock-Up Agreement of which the undersigned is the record holder, and, with respect to shares of Common Stock or other securities subject to this Lock-Up Agreement of which the undersigned is the beneficial owner but not the record holder, the undersigned hereby agrees to cause such record holder to authorize the Company and its transfer agent, during the Lock-Up Period, to decline the transfer of or to note stop transfer restrictions on the stock register and other records relating to such shares or other securities.

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If (i) the Company notifies you in writing that it does not intend to proceed with the Offering, (ii) the registration statement filed with the Commission with respect to the Offering is withdrawn or (iii) for any reason the Underwriting Agreement shall be terminated prior to the “time of purchase” (as defined in the Underwriting Agreement), this Lock-Up Agreement shall be terminated and the undersigned shall be released from its obligations hereunder.

Yours very truly,

Name:

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