* Page reassures staff, "nothing seriously wrong"
* Governance experts say Street may need more details later
* CEO's medical condition still not known
SAN FRANCISCO, June 22 (Reuters) - Google Inc CEO Larry Page, who plans to skip several high-profile events in coming weeks after losing his voice, told employees there was "nothing seriously wrong with me," according to a source who had seen an internal staff memo.
Page sat out his company's annual shareholders' meeting on Thursday. The 39-year-old Google co-founder is resting his voice because of an unspecified condition, and he will miss Google's annual developer conference next week as well as its quarterly results announcement next month, executives said on Thursday without elaborating.
Page continues to run Google's business, Executive Chairman Eric Schmidt told attendees at the shareholder meeting on Thursday. But Page's prolonged absence from the public spotlight raises questions about his condition, and the company's obligation to highlight issues of concern to shareholders.
Corporate governance experts say Google has met minimal disclosure requirements but will face increasing pressure while Page remains out of sight.
On Friday, Google's shares rose 1.1 percent to $571.48, lifted along with the rest of the Nasdaq.
"It gets them over the first disclosure hurdle, that is they've alerted shareholders to the fact he's going to have this health effect," said James Post, a professor of management at Boston University who focuses on corporate governance issues.
"It's OK for them not to say that. As more information emerges from other sources, the tough questions still lie ahead, and there will be continued pressure to keep answering those tough questions."
Google would not comment on its CEO's medical condition on Friday.
Page, co-founder Sergey Brin and Schmidt control a majority of the Internet company through special shares that give them more voting power.
That capital structure, emulated by a new generation of Web companies from Facebook Inc to Zynga Inc, grants founders enormous influence over their companies, and also entwines their fate with the corporations they lead.
Wall Street analysts mostly took the news of Page's extended absence in stride, though some expressed concern about the lack of information.
"It's the number one thing I'm concerned about today just because there's so little data available," said BGC Partners analyst Colin Gillis.
JP Morgan analyst Doug Anmuth noted that Page has not posted any messages to his Google+ profile since May 25.
"We have no specific reason to think there is anything more to Larry's condition, but we find it odd that the company would already rule him out of the 2Q call, which is likely still a few weeks away," Anmuth wrote to clients late on Thursday.
"This could raise some questions among investors."
Simon Best, a head and neck surgery specialist at the Johns Hopkins Voice Center, said most cases where doctor might order a patient to rest their voice involved either a vocal chord hemorrhage or bleeding, or throat surgery of some sort.
"We actually very rarely put people on complete voice rest where they are not cleared to talk or allowed to talk," West said. "There are probably some practice differences between physicians and whoever is treating him, but there are only two scenarios where we put people on voice rest: if they've had vocal cord surgery, or if they've had a vocal chord hemorrhage."
Best, who has not treated Page, said hemorrhages were easily treatable, but a wide variety of conditions might necessitate surgery.
The Wall Street Journal first reported on the details of Page's internal memo on Friday.