Utilize your financial knowledge, give your answer or opinion to the input question or subject . Answer format is not limited.

Why would a tender offer be less than the market price?
Rational shareholders wouldn't accept such an offer. The company making the offer is simply trying to get a deal with questionable — though not illegal — tactics. Your answer is actually in the link you provided.  Quoting from the fourth paragraph [emphasis is mine]:  The SEC has cautioned investors about mini-tender offers, noting that   "[s]ome bidders make mini-tender offers at below-market prices, hoping   that they will catch investors off guard if the investors do not   compare the offer price to the current market price." The SEC's tips   for investors regarding mini-tender offers may be found on the SEC's   Web site at http://www.sec.gov/investor/pubs/minitend.htm. There's a lot more information at the SEC web page mentioned.  One part I'll highlight from the SEC web page mentions another reason for a mini-tender: Investors need to scrutinize mini-tender offers carefully. Some   bidders make mini-tender offers at below-market prices, hoping that   they will catch investors off guard if the investors do not compare   the offer price to the current market price. Others make mini-tender   offers at a premium – betting that the market price will rise before   the offer closes and then extending the offer until it does or   improperly canceling if it doesn't. You'll also find a lot more information at Wikipedia - Mini-tender offer.