A meeting at Facebook’s US headquarters involving cake and Coca Cola prompted Neptune founder Robin Geffen to sell his shares in the technology giant.
Mr Geffen runs the £474m Neptune Balanced fund, which invests in bonds and equities with 30 per cent of the fund invested in information technology.
Speaking at a lunch in London Mr Geffen said: "I went to California, and it is one of the three worst meetings I have had in my working life.
"When we got there, we went to three different buildings before anyone could tell us where the investor relations department was. And everywhere we went, there were lots of people high fiving us and trying to give us Coca Cola and cakes, and it certainly didn’t seem like anyone was doing any work.
"Having seen that, I’m not surprised the number of employees has gone up, but it seems the only strategy anyone has for the business is whatever Mark Zuckerberg thinks up in the morning.
"As we were leaving the meeting, I said to James [Dowey, Neptune's chief investment officer] that we have to sell the shares, and then a little while later the shares fell a lot."
Facebook's share price has fallen by around 27 per cent since July, with a large part of that fall coming in July after the social media giant revealed growth had slowed in the wake of the Cambridge Analytica scandal.
Donald Maxwell-Scott, technical investment manager at wealth manager Rowan Dartington said the valuations at which Facebook and other large technology companies trade bear no resemblance to the earnings being achieved by those businesses.
Mr Geffen said he is also invested in Japanese and emerging market equities, and uses put options for downside protection.
He added that he was shunning bonds because he felt the next recession would come at a time of high inflation, rather than deflation, and these recessions typically lead to both equities and bonds falling in price.
Jonathan Davis, who runs Jonathan Davis Wealth Management in Hertford said the prospect of higher inflation meant conventional bonds would perform badly because they had a fixed rate of interest, but bonds which are linked to rising interest rates represent an opportunity for investors.
Over the past three years the Neptune Balanced fund has returned 42.3 per cent while its sector, the IA Mixed Investment 40-85 Per Cent Shares, returned 31.1 per cent.
Meanwhile over the past year the fund has returned 12.2 per cent and its sector has returned 5 per cent.