Stanford Law School Professor Joseph Grundfest, who is co-director of the university's Rock Center for Corporate Governance, said many of the maneuvers Yahoo and Microsoft have made so far represent textbook merger strategies.

"This is almost the traditional M&A hokey pokey: There are a set of steps that are entirely predictable," said Grundfest, a former Securities and Exchange Commissioner.

But he said the possibility of side-deals short of a merger between Microsoft and Yahoo, the emergence of Google as a potential alternate partner for Yahoo and deal spoiler for Microsoft, and the entry of corporate raider Icahn, have combined to create "almost a unique form of the hokey pokey."