Longs Sticking to CVS Merger Plan

CtW's Clayton has already challenged most of those arguments. On the key matter of antitrust issues and possibly regulatory risks, for example, Clayton feels that Walgreen has actually gone a step further than CVS.

Notably, he stressed, Walgreen has pledged to assume all regulatory risks involved with the deal so long as it doesn't require the company to divest itself of stores representing more than 40% of Long's operating income. In contrast, he noted, CVS could have backed away if divestitures cost it just 30% of Longs' operating income instead.

"Now that a potentially superior proposal has surfaced, we believe the Longs board must take immediate steps to cure this flawed process and ensure that shareholders receive full value for their investment," Clayton wrote in a recent letter to the company's directors. Ultimately, "we believe that only an open, competitive auction will cure the flawed process that has so far characterized the Longs board's effort to sell the company, and ensure that shareholders receive the best available terms."

Clayton wants Longs to start by establishing a special committee that includes only independent members of its board. With the help of an independent financial advisor -- whose fees are not linked to a particular deal -- he urges that committee to go seek out other offers and recommend the best one it can find.

"It's time for the board to step up and take control of this process," Clayton told TheStreet.com on Wednesday. If that happens, "we may well end up with a better price than even $75 a share."