I covered this in November 2006, Grandfathered Bids in Yahoo! Search Marketing Do Not Carry To Panama.
But recent questions came up at WebmasterWorld asking;
I can't find if the grandfathered bids are meant to be respected after the upgrade or not? All min ehave been set to the minimum 0.10 when before many were 0.05, 0.07 etc.
So just another heads up, no more grandfathered bids with the release of panama.
Thanks for your feedback and questions on grandfathered bids and the minimum bid requirement.
After years of supporting legacy bids that were lower than our current minimum bid requirement of $0.10, we now require all keyword bids to be at least $0.10 for all accounts that have been upgraded to the new search marketing system .
To learn more about bidding and Yahoo!’s new ranking model in the U.S., please check out the following tutorial:
Forum discussion at WebmasterWorld.