Martin Marietta Materials, Inc. (NYSE:MLM) may be a stock worth watching today after Daniel Loeb's Third Point disclosed a 5.4% stake in the company, according to a 13D filing with the SEC. Daniel Loeb and his Third Point are well known (and well regarded) within financial circles as activist investors who are quite outspoken - having called CEO's everything from "Chief Value Destroyers" to "toothless cronies". However, aside from his often entertaining (yet extremely insightful) letters, Daniel's fund has averaged an enviable 30% annualized return over the last ten years, making his fund one of the most successful on Wall Street. And with over $2.1 billion currently invested, his fund is definitely one worth keeping an eye on - especially in early stage investments like MLM (in which he only holds 5%). You can view a complete listing of their funds holdings as of November by looking at their recent 13F filing with the SEC.

Currently, Item 4 (purpose of the transaction) of his MLM 13D filing simply indicates a generic investment in the company:

"The purpose of the acquisition by the Funds of beneficial ownership of the securities is for investment. The acquisition was effected because of the Reporting Persons’ belief that the Company represents an attractive investment based on the Company’s business prospects. The Reporting Persons are engaged in the investment business. In pursuing this business, the Reporting Persons analyze the operations, capital structure and markets of companies, including the Company, on an ongoing basis through analysis of documentation and discussions with knowledgeable industry and market observers and with representatives of such companies (often at the invitation of management). Depending on prevailing market, economic and other conditions, one or more of the Reporting Persons may from time to time, among other things, hold discussions with third parties or with management of such companies (including the Company) in which the Reporting Persons may suggest or take a position with respect to potential changes in the operations, strategy, management or capital structure of such companies as a means of enhancing shareholder value. Such suggestions or positions may relate to one or more of the transactions specified in clauses (a) through (j) of Item 4 of Schedule 13D of the Exchange Act, including, without limitation, such matters as disposing of or selling all or a portion of the company or acquiring another company or business, changing operating or marketing strategies, adopting or not adopting certain types of anti-takeover measures and restructuring the company’s capitalization or dividend policy. The Reporting Persons presently do not have any plans or proposals that relate to or would result in any of the actions required to be described in Item 4 of Schedule 13D. Each of the Reporting Persons may, at any time, review or reconsider its position with respect to the Company and formulate plans or proposals with respect to any of such matters." (Read More)

Third Point averaged in at around $90 per share, meaning that they are currently sitting on a 10%+ profit on their investment; however, given the fact that this is still an early stage investment for them (only buyers since October) and given that the company is in the construction industry, Loeb is probably expecting much more significant upside on this investment with his most recent purchase on December 1st. Any changes in his position can be seen in future 13D/A filings with the SEC. This is definitely a stock to keep a close eye on in the coming months!

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