* GfK Verein says boards have no plans to approve sale
* German magazine had said it was eyeing a sale or merger
* GfK Verein: Will do everything it can to support GfK
* Shares drop 3.8 pct to bottom of SDAX index (Adds shares, further GfK Verein comment, background)
FRANKFURT, Aug 26 (Reuters) - The majority owner of Germanmarket research firm GfK said on Friday it was notconsidering a sale of shares, rejecting a magazine report thathad said it was eyeing a merger or sale of the group.
"The bylaws of (majority owner) GfK Verein show that a sharesale is not easily done, as the executive board and the advisoryboard would have to approve such a plan, and they are not doingthat," GfK Verein President Hubert Weiler said in a statement.
German weekly WirtschaftsWoche reported on Thursday thatGfK's U.S. rivals Nielsen Holdings and IMS Health as well as WPP unit Kantar were interested inGfK Verein's 56.5 percent of GfK.
GfK Verein's denial on Friday pushed the shares down 3.8percent to 28 euros, wiping out the previous day's gains andmaking them the biggest decliners on Germany's small-cap index.
GfK's stock has fallen by 20 percent this month after itwarned on 2016 profits for a second time and its chairman andchief executive both unexpectedly resigned due to a falling-outwith GfK Verein over strategy.
GfK on Thursday named a new chairman from the ranks of itsmajority owner, who GfK Verein said on Friday had alreadystarted to analyse the situation at the group.
"GfK Verein is backing GfK for the long run and will doeverything possible to ensure the company returns to asustainably successful path," GfK Verein's Weiler said. (Reporting by Maria Sheahan; editing by Victoria Bryan andJason Neely)