Manchester United's share value rose by $240 million (£171 million) in the first hour of trading after the announcement of the European Super League, The Athletic reported.
United were among the 12 major European clubs who announced their intention to form a breakaway competition on Sunday night.
The teams, who made a joint statement to confirm plans of forming a new European Super League, consisting of the following clubs: AC Milan, Arsenal, Atletico Madrid, Chelsea, Barcelona, Inter Milan, Juventus, Liverpool, Manchester City, Manchester United, Real Madrid and Tottenham Hotspur.
The Old Trafford club's share value has risen by more than eight per cent since the opening of trading in New York on Monday morning.
That has seen each share grow from $16.17 at the close of trading on Friday to a value of $17.48 at 3 pm BST on Monday.
The clubs say that 15 founding clubs — the 12 who have reached the agreement plus three who they expect to join — will be joined by five other teams who qualify each season.
They say the games will be played in midweek, starting in August, with teams playing home and away fixtures in two groups of ten, with the top three in each group automatically qualifying for the quarter-finals.
Teams finishing fourth and fifth will then compete in a two-legged play-off for the remaining quarter-final positions. A two-leg knockout format will be used to reach the final at the end of May, which will be staged as a single fixture at a neutral venue.
The clubs said that a women's league will also be launched "as soon as practicable" after the start of the men's competition, but provided no further details.