NEW YORK ( TheStreet) -- Takeover speculation boosted shares of several online brokers including E*Trade Financial ( ETFC - Get Report) and TradeStation ( TRAD).

E*Trade shares popped 5.7% earlier in the day on renewed speculation that the online brokerage firm could be acquired. The stock closed up 2.3% to $15.30 on strong trading for the day.

Rumors on several trading websites said that rival Charles Schwab ( SCHW - Get Report) was looking into buying E*Trade for roughly $22 a share -- that's a 47% premium to E*Trade's closing stock price on Thursday.

E*Trade has been the subject of M&A speculation for years, however it was TD Ameritrade ( AMTD - Get Report) that more often came up as a possible suitor.

Both Schwab and E*Trade said they do not comment on rumors or speculation.

Separately, shares of TradeStation surged nearly 10% at one point after one activist shareholder, and rival trading firm, took a large stake in the company.

According to a Securities and Exchange Commission 13-D filing on Thursday, IBG Holdings, which owns Interactive Brokers Group ( IBKR - Get Report), and its founder and chief executive Thomas Peterffy, bought 2.56 million shares of TradeStation for roughly $17 million.
Interactive Brokers Group founder and chief executive Thomas Peterffy

One market participant, who declined to be named, said that rumors are spreading that the share purchase could be the beginning of a hostile takeover between rivals. Interactive Brokers "tends to be bottom fishers when it comes to acquisitions," the participant said via email.

According to the filing, the shares were acquired for "investment purposes." At the time of the filing, Peterffy did not have any "present plans or proposals which would relate to or would result in any transaction, event or action ... but the Reporting Persons will continue to analyze their investment in the company on an ongoing basis."

Interactive Brokers is an "automated global electronic market maker and broker specializing in routing orders and executing and processing trades in securities, futures and foreign exchange instruments on more than 80 electronic exchanges and trading venues around the world," according to the company.

Interactive Brokers provides liquidity at the various marketplaces. As a broker it provides professional traders and investors with electronic access to stocks, options, futures, foreign exchange products, bonds and mutual funds, the company says.

TradeStation offers similar brokerage services to professional traders.

TradeStation released monthly metrics on Tuesday in which October daily average revenue trades, or DARTs, dropped 13% compared to a year earlier, but rose 4% from the prior month to 75,850. Client assets rose 14% year over year to $2.28 billion.

Interactive Brokers said October average daily trades rose 3% and 7%, to 376,000.

TradeStation shares were most recently trading up 7% to $6.09 on more than double the normal trading volume. Shares of Interactive Brokers hit a new intraday 52-week-high on Friday of $19.19. The stock closed up 1.1% at $19.08. Schwab's stock rose 1.6% to $16.10.

To contact the writer of this article, click here: Laurie Kulikowski.

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