Last year CVS, Inc. (NYSE: CVS), a pharmacy chain, made a $21 billion offer for CareMark Rx Inc. (NYSE: CMX), a pharmacy benefits manager (PBM). As I posted in December, Express Scripts, Inc. (NYSE: ESRX), another PBM, came along with a $26 billion offer but CMX turned it down. Now BusinessWeek reports that CMX shareholders have filed suit against CMX's directors alleging "breach of duty."

This deal really makes my blood boil. And I've said so here and here. Why? Because CMX shareholders are getting a a lower price for their stock so CMX management can avoid paying the price for its scandals -- including a whopper of an options backdating problem.

So I am thrilled to learn about this lawsuit alleging that CMX's top management and directors accepted an inadequate takeover bid from CVS in large part because the deal protected them from charges of improper backdating of stock options.

Ever since the hostile takeover wars of the 1980s, people have been preaching about maximizing shareholder value against the interests of entrenched management. This CMX deal proves that this battle has not yet been won.

Peter Cohan is President of Peter S. Cohan & Associates, a management consulting and venture capital firm. He also teaches Management at Babson College and edits The Cohan Letter. He has no financial interest in CareMark Rx, CVS, or ExpressScripts.