Update: Baillie Gifford has hiked its valuation of SpaceX for the second time in four months amid reports that the Elon Musk rocket and satellite group has filed for an initial public offering (IPO) in the US that could value it at up to $1.75trn (£1.3trn), up from the $800bn it doubled at the end of last year.

While the Edinburgh-based investment group did not disclose what it valued SpaceX at, a flurry of updates last night from its four investment trusts with stakes in the company added a total of £1.1bn to their net asset values (NAV).

SpaceX now accounts for 19.3% of £12.8bn Baillie Gifford flagship Scottish Mortgage Trust (SMT), up from 15.4% on 28 February, according to its update.

SpaceX now represents 14.9% of Baillie Gifford US Growth (USA), up from 11.9% at the end of February; 20.4% of Edinburgh Worldwide (EWI), up from 16.3%; and 12.8% of Schiehallion (MNTN) up from 10.5%.

According to reports from Bloomberg and the Wall Street Journal, SpaceX has “confidentially” filed for an IPO to give regulators time to consider the move.

Scottish Mortgage said the rise in valuation had been reflected in its (cum fair) NAV per share which at 31 March stood at 1316.12p, up 74.83p from 1241.29p on the previous day.

With over a billion (1,078,166,806) shares in issue that represents an increase of £748m in value for Scottish Mortgage alone. However, not all of that is due to SpaceX. The gain will also reflect movements in the shares of its 48 publicly listed holdings, which given the volatility from the Middle East, could be considerable. The same applies to the other trusts.

For £806m Baillie Gifford US Growth, whose (cum par) NAV per share at 31 March was 301.12p, up 16.88p from 284.24p on 30 March, its 276.7m of shares have registered a £46.7m one-day gain.

The £783m Edinburgh Worldwide made a £56.4m gain from the 16.3p rise in (cum par) NAV per share to 227.47p at 31 March.

Schiehallion, a £1.9bn dollar-based fund that publishes a monthly valuation, has seen a $395m (£299m) gain from the 3.95 cents rise in its (cum) NAV per share to 176.62 cents at 31 March. However, that will also include movements in its other holdings since 27 February, the day before the US and Israel launched their war on Iran. The private equity fund holds around 20% of its assets in companies that have floated on the stock market.

There were no big movements in any of the trust’s shares this morning. SMT eased 5p to £12.53 to a 4.8% discount below the new NAV.

EWI, which faces a possible wind-down, was steady at 226.4p, 0.5% below NAV. Its board is encouraging shareholders to sell all their shares in a tender offer before hostile hedge fund Saba Capital possibly seizes control at this month’s annual general meeting.

USA added 3.2p or 1% to 294.2p, a 2.3% discount to NAV.

Schiehallion edged 0.1% to $1.88, 6.5% above NAV after a first quarter in which the shares rallied 27%. Fund manager Robert Natzler yesterday told journalists the company was considering taking advantage of its share price premium to raise more funds.

Our view

James Carthew, head of investment company research at QuotedData, said: “This latest write up of SpaceX coincides with and therefore was presumably triggered by SpaceX filing for an IPO yesterday. The filing is said to target a valuation of $1.75trn for the company which would imply further upside to come on this holding. However, the sheer size of the issue (over 2.5 times the largest previous IPO), the challenging rating (reportedly 67 times revenue), and the possibility that insiders will not be locked in, could, I think, weigh on the post IPO price.”

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