That Letter Offering to Buy Your Stock? Think Twice.

Another company, Tutanota, has made a spate of mini-tender offers since last summer, soliciting shareholders of companies including PayPal, Adobe, Disney, Microsoft, Alibaba and Bank of America.

Its offer for PayPal was $125 per share — as long as the stock was trading above that price on the last day of the offer period. The offer also noted that Tutanota expected to extend the offer several times, “until the market price exceeds the offer price,” and that the offer was dependent on Tutanota’s “obtaining all financing necessary” to fund it.

PayPal, whose stock closed at $102 on Thursday, advised shareholders in a Feb. 25 statement to reject the offer. “PayPal does not endorse Tutanota’s unsolicited mini-tender offer and is not affiliated or associated in any way with Tutanota, its mini-tender offer or its mini-tender offer documents,” it said.

Tutanota, which describes itself as “a private investment company that specializes in investing in publicly traded securities whose value it expects to appreciate over a 12-month period,” couldn’t be reached for comment. No one responded to an email address provided in the offer, or to messages left at a phone number that was answered by a recording.

(A spokeswoman for Tutao, a German company that provides a secure email service called Tutanota, said in an email that it had “no affiliation with Tutanota L.L.C. whatsoever.”)

Companies can be in an awkward position when shareholders receive mini-tender offers. According to the S.E.C., companies must notify their shareholders of tender offers once they become aware of them. But because bidders in mini-tender offers aren’t required to notify the target, the companies may not know about them.

Here are some questions and answers about mini-tender offers:

Bidders generally don’t label their offers as mini-tenders, perhaps because of their dubious reputation. The S.E.C. advises reading the offering document carefully and checking with the bidder or your broker or financial adviser, if you have one. If the bidder is seeking less than 5 percent of the company’s shares, the S.E.C. says, “you’re dealing with a mini-tender offer, and you should proceed with caution.”