Mubadala Investment, Abu Dhabi’s sovereign wealth fund, is seeking to raise $1.91 billion from an unregistered block sale of GlobalFoundries shares, according to people familiar with the matter, Bloomberg reported.

GlobalFoundries shares dropped 6.9% in extended trading.

The shares are being offered for $86.30 to $86.80 each, the people said. Morgan Stanley is working on the offering, the people said.

The deal is being marketed at as much as a 4.1% discount to Tuesday’s closing price of $89.96. The share sale includes a 60-day agreement restricting further sales by Mubadala, the people said.

Mubadala sold 22 million shares in a block trade, reducing its stake to 400 million shares or 73% of GlobalFoundries, it said in an emailed statement late Tuesday confirming a Bloomberg News report. The sovereign investor remains highly committed to GlobalFoundries’ strategic direction, Camilla Languille, co-chief executive officer of private equity at Mubadala, said in the statement.