IBM is trading at about $182 at the moment.

There is a tender offer from a company to purchase IBM shares at $170. Why would shareholders accept this offer of $170, when they could just sell the shares in the open market for $182? Why would the company make an offer at $170?

[IBM Form 8-K filing](https://www.sec.gov/Archives/edgar/data/51143/000110465913080066/a13-23402_18k.htm)