The investment group, Sports Alpha Capital, had previously been in talks over a takeover of fellow League Two side Colchester United earlier this year before pulling out following initial discussions.
Pato, who is involved with the consortium but not fronting it, retired from playing in 2023, some years after his best spell in the game – five and a half seasons at AC Milan that yielded 63 goals in 150 appearances and a Serie A title in 2010-11.
A loan spell at Chelsea followed in the second half of 2015-16, arranged from Corinthians, during which he opened his account with a penalty in a 4-0 away win over Aston Villa on his debut.
The news follows chairman Kelvin Thomas's confirmation last month that a "well-funded" group's proposed investment had been "pretty much agreed."
Northampton were relegated to the fourth tier last season after finishing bottom of League One. The club's finances remain a pressing concern: April's accounts showed a pre-tax loss approaching £3m, and Thomas has previously indicated the takeover would wipe out Northampton's existing debts entirely.
On the pitch, new boss Chris Hogg – appointed in May – has already added seven fresh faces to his squad this summer, headlined by striker Matty Warhurst's arrival from Manchester City and midfielder Connor Lemonheigh-Evans's move from MK Dons.
The proposed investors were present at Sixfields for Northampton's pre-season friendly against Coventry City, fuelling speculation that a deal was edging closer, while Pato's decision to begin following the club's official account on Instagram had already prompted supporters to draw their own conclusions in recent days.
Thomas has previously said he hoped the takeover would be finalised before the start of the new League Two season, though he has also stressed that the final timeline is largely out of the club's hands, with regulatory approval from the EFL and independent football regulator among the remaining steps before any deal can be completed.