Twitter Inc. shares rose the most in five weeks on an endorsement from Citron Research and renewed speculation the social-media company may be an acquisition target.

The research firm in a tweet called 2018 “the year for” Twitter, put a target price of US$35 on the stock and speculated that Chinese social-media giant Tencent Holdings Ltd. would buy the San Francisco-based company. Earlier, Twitter gained as unconfirmed takeover speculation among traders pointed to Salesforce.com Inc. as a possible buyer.

Twitter jumped 9.5 per cent to US$24.27 at the close in New York, the biggest single-day increase since Dec. 18.

“I think Twitter is at the early onset of a pretty meaningful turnaround in revenue,” BTIG analyst Richard Greenfield said in a phone interview. “It wouldn’t shock me for someone to try to buy them before it happens.”

The company reported surprisingly positive third-quarter results in late October and received upgrades and higher target prices from at least six Wall Street analysts, fueling a 40 per cent stock rally through mid-January. Shares declined 5 per cent the past three days after Twitter said Chief Operating Officer Anthony Noto had left to become chief executive officer at Social Finance Inc.

Salesforce.com CEO Marc Benioff said in October 2016 that he would not make a play for Twitter because it did not mesh well with his business software company. Twitter and Salesforce declined to comment on Friday’s speculation. Bloomberg LP produces a breaking news network for Twitter.

The company has made positive strides since deal talks first surfaced in 2016. Greenfield said user growth and advertiser spending trends have improved while the company has prioritized combating abuse and harassment on the platform.

Twitter may be hard pressed to pass up a bid “meaningfully above US$30” without any controlling shareholders, he said.