Toshiba Corp. walked away from potential private equity buyout offers at a substantial premium, as well as advanced talks for a minority stake from Canada's Brookfield Asset Management, according to three people familiar with the matter.

Toshiba's decision to not pursue either course — some details of which have not been previously reported — and instead focus on a plan to split itself in three, has widened the gulf between the conglomerate and a number of its hedge fund investors, according to the people, all of whom declined to be identified because of the sensitivity of the issue.

Some investors take issue with Toshiba's argument that a three-way split would create greater value than a private equity deal, given the company never formally solicited buyout bids, the people said. As such, some investors question the transparency of Toshiba's ongoing strategic review.