By Svea Herbst-Bayliss
BOSTON, Dec 9 (Reuters) - Billionaire investor William Ackman's hedge fund Pershing Square Capital Management said Monday it bought shares in testing equipment company Agilent Technologies Inc, only its second new investment this year as the fund has reported a 51% return.
Agilent Technologies' stock price jumped nearly 5% in after-hours trading after Ackman's investment was made public in a regulatory filing. Ackman's $7 billion fund earlier in the year bought Berkshire Hathaway Inc shares.
The filing did not say whether the Agilent investment will be active or passive, and Ackman's spokesman declined to comment. The filing showed that Pershing Square owned 2.9 million shares at the end of September and did not say how big the position is currently. At Monday's stock price, that stake would be worth $246 million.
Ackman, who cemented his reputation as one of the world's most widely followed activist investors with bets on Canadian Pacific and Chipotle Mexican Grill, among others, told investors last month that he had a new position but declined to name it.
That hint sparked heavy speculation about the possible target with guesses ranging from Adobe Inc to Yum Brands, but the name was successfully kept under wraps.
The new position was announced at the end of a banner year for Ackman when his publicly traded fund has gained 51%.
Agilent, which serves the life sciences, diagnostics and applied chemical markets, was created two decades ago when it was spun off from Hewlett-Packard.
In the last year, its stock price has climbed 15.63% while the Standard & Poors 500 index has gained 19%. The company's biggest investors include index funds Vanguard Group, BlackRock and State Street as well as T.Rowe Price Associates and Wellington Management.
Ackman's firm has not yet made a so-called 13D filing which is required if an owner's stake exceeds 5%.
For roughly two years, Ackman has kept a lower profile and worked to recapture his reputation as a skillful investor after certain bets, including a 2015 investment in Valeant Pharmaceuticals, soured, leaving the firm with heavy losses that sparked investor exits.
He stopped jetting around the world to visit investors. Instead he concentrated on finding new ideas and promised to update investors at periodic dinners and on conference calls.
The Berkshire bet sparked questions about how active Ackman still is and what he is doing to prod management to perform better. He acknowledged that he has not spoken Berkshire's founder Warren Buffett following his recent investment.
(Reporting by Svea Herbst-Bayliss; editing by Jonathan Oatis and Cynthia Osterman)