Twitter granted varying amounts of restricted stock depending on when the employees started working, intending to make up for the value they lost since joining the company, it said, citing people familiar with the matter.

Since the fall, the company has also been offering cash bonuses to some employees ranging from $50,000 to $200,000 as an incentive to keep them around for another six months to a year, it added.

Twitter has been struggling to keep talent at the company as stagnant growth and falling stock have raised questions over the company’s future.

Four top executives left the company in January, the biggest leadership changes since Jack Dorsey returned as chief executive last year. Dorsey has been trying to answer questions about the service’s vision and direction ever since.

After returning to the company he founded, Dorsey said in October he is giving a third of his stock in the company, about 1 percent, to the employee equity pool.

Later that month, Dorsey spoke about “hiring and investing in talent” and the need for “bold rethinking.”

Twitter could not be reached for comment outside regular U.S. business hours.