Andrew Bracey, finance director of Ocado, has quit to join the recruiter Michael Page, sending its shares down by nearly 4% today.
Ocado used the departure of Bracey, who will take up the same role at Michael Page, to unveil a wider shake-up of its top team, which includes a new role for one of its co-founders, Jason Gissing.
Bracey joined loss-making Ocado in November 2009 ahead of its controversial flotation at 180p the following July.
The online grocer, which delivers Waitrose grocers, has never made a pre-tax profit, and warned on profits just before Christmas, as it admitted its warehouse in Hatfield, Hertfordshire, was struggling with "capacity constraints" to meet demand for its services.
Shares in Ocado tumbled by 3.1p, or 3.5%, to 84.6p, valuing the company at £472.5 million.
The online grocer paid Bracey £434,000 in the year to November 28 2010, including a salary of £281,000 and a bonus of £150,000.
He currently owns 820,000 shares in Ocado. But Bracey also had nearly 8 million share options across various schemes.
All of these share options are currently under water.
The schemes vary between having an exercise price of 90p until 2017, and a hurdle price of £2.28 until 2019.
However, Bracey will retain 4.3 million share options despite, his departure in April.
He said: "My decision to leave the company has been a tough one to make, but I have been presented with a great opportunity I intend to retain my shareholding."
Gissing, the current executive director of people, culture and communications, will take the new board position of commercial director, putting him in charge of Ocado's retail activities, including buying and supplier relationships.
Neill Abrams, its director of legal and business affairs, will take over his responsibilities for human resources, while head of technology Mark Richardson has been promoted to the new role of operations director.
Ocado grew sales by 10.8% to £198.2 milion over the 16 weeks to November 27.
Philip Dorgan, analyst at Panmure Gordon, said: "Following the share price rise last week, we think that this is a good time to sell the shares.
"Ocado is some way from making a profit and the expected acceleration in sales growth this year looks way too ambitious."
