(Telecompaper) Yahoo shareholder Starboard Value has warned the company against making any large acquisitions. Jeffrey Smith, managing member of Starboard Value, wrote to Yahoo chief executive Marissa Mayer after rumours that the company could be considering a deal to buy cable TV channels including Scripps Networks Interactive and Time Warner's CNN, the Financial Times reports. The shareholder, who lobbied for Yahoo to tie up with AOL in a previous letter, said it was "increasingly concerned" that the company could use the proceeds from the sale of some of its stake in Alibaba to make a big purchase. Smith warned that a large acquisition or a spin-off of Asian assets in return for cash, rather than a more tax-efficient restructure of Yahoo's remaining stakes in Alibaba and Yahoo Japan, would "be a clear indication to us that significant leadership change is required". Other large shareholders have also expressed "serious concerns" with the rumours of a sizeable deal, he claimed in the letter. Yahoo did not comment on the letter.