In a statement, Nasdaq said it contacted the Internet company and requested that it issue a public statement specifying any corporate developments that might explain "unusual market activity" in its stock.
Shares in the Net advertising firm closed today at 64, up 14.3125, scoring a new 52-week high. More than 3.8 million shares changed hands--ten times the average daily volume of 350,590.
Nasdaq makes similar inquiries of stocks from time to time. The sharp run-up in Internet stocks of late--to unprecedented levels--may focus more attention on the sector in the future.
Nasdaq has an active surveillance arm that watches for unusual trading activity, said Michael Whitehouse, a Nasdaq spokesman. "When it finds any unusual behavior such as a jump in stock, or unusually high volume, we notify the company and ask if there is any material news that has not been disseminated to the marketplace," he said.
Whitehouse added that DoubleClick had no comment. A company executive declined to comment for this story.
One factor that may have contributed to DoubleClick's surge today is its announcement in a press release yesterday that it has the "third largest audience reach on the Internet behind America Online and Yahoo, according to Media Metrix," a Net research firm.