Virgin Galactic Holdings (SPCE -6.28%) founder Richard Branson has sold more than $150 million worth of the company's stock in recent days, the second high-profile investor to shed shares of the space-tourism company in recent weeks.

Branson and entities affiliated with his Virgin holding company sold 5.584 million shares of Virgin Galactic, according to a regulatory filing first reported by CNBC. The shares were sold at prices ranging from $26.85 to $28.73, for total proceeds of $150.3 million.

Interior of Virgin Galactic's space ship.

Image source: Virgin Galactic.

Branson created Virgin Galactic and took it public in 2019 via a merger with a special purpose acquisition company affiliated with Chamath Palihapitiya. Last month Palihapitiya, who remains chairman of Virgin Galactic, sold about $213 million worth of the stock.

The sales come at a delicate time for Virgin Galactic. The company has hundreds of clients signed up to pay $250,000 for a brief trip to the edge of space but is behind schedule in getting them there. Virgin Galactic had originally hoped to initiate service last year, but a combination of pandemic-related delays and some testing setbacks has pushed back that timeline.

Virgin Galactic also recently lost chief space officer George Whitesides, the one-time chief of staff at NASA, who left to pursue potential opportunities in public service.