Macrovision Corp. investors showed their displeasure with the company's pending $2.4 billion bid for television listings provider Gemstar-TV Guide International Inc. by stampedng for the exits soon after the deal was announced in December.

Now, some are starting to get vocal about it.

Activist hedge fund Loeb Partners Corp. of New York on Thursday disclosed in a letter to Macrovision management that it will vote its 2.1% stake in the company against the deal, saying the potential advantages of the deal "seem vague" and the combination will not turn the company into a "show-me stock."

Santa Clara, Calif.-based Macrovision provides analog copy protection for the entertainment industry, and software installation, update and license management technology to software publishers and enterprises. Shares of the  company traded at $17.39 Thursday, a decrease of roughly 30% since the deal was announced Dec. 7 after dropping 21% that day. Macrovision shares actually got a boost on Thursday after Jefferies & Co. upgraded the stock to buy from hold.

In a research note, Jefferies analyst Ross MacMillan placed a $23 price target on the stock, regardless of whether the deal is approved. Though he did not speculate on the outcome of the shareholder vote, MacMillan wrote that Macrovision's stock "looks very cheap" in the case of a failed acquisition.

"Much depends on what the proxy filing says and what the advisory services decide," MacMillan wrote. "Macrovision management has met all major shareholders on both sides and we think there has been a gradual improvement of understanding of the deal."

Mark Harding, an analyst with Maxim Group, said he got a better sense of why the deal makes strategic sense for Macrovision after spending time with Gemstar executives at the Consumer Electronics Show in Las Vegas this week.

"Previously, I was negative on the business synergies as well as the financing," he said. "Now I'm just very cautious about the financing. It's a very complex financing arrangement requiring divestiture of noncore assets, as well as debt financing, and the debt market is not a favorable market right now."

Macrovision's chief financial officer, James Budge, declined by e-mail to comment on the Loeb letter, but added that "investors are free to make their own decisions."

"We continue to believe that this is a compelling business combination," he added.

The challenge for Macrovision execs will be showing investors how the acquisition will benefit the company, Harding said.

When the deal was announced, the companies said the merger would allow consumers to pull up a guide on their TV and receive personalized content and information regarding TV shows, read movie reviews before purchasing or renting a film, view personal photos or tap into their music library.

"I think there needs to be better communication between the company and investors as to the synergies, but I'm starting to warm to that aspect," Harding said.

Investors also need to be aware that if they vote down the deal, the Macrovision business will not be the same going forward as it was before the acquisition, he added.

The company has been de-emphasizing its software division because it is not seen as core to its long-term strategy, and has said it would sell this business should the deal close. MacMillan valued Macrovision's software division at $300 million.

The deal values Los Angeles-based Gemstar at $5.53 a share, 17% more than the company's share price of $4.77 on Thursday, suggesting arbitrage traders still see a lot of risk with the deal going through.

Loeb Partners did not return a phone call seeking comment.