Peak6 Investments is led by Matt Hulsizer, the owner of NHL ice hockey side Minnesota Wild.
Hulsizer and colleague Jay Coppoletta have established a relationship with Bournemouth over the last 15 months.
"The club is confident this partnership will further strengthen its ability to compete with the very best," Cherries chairman Jeff Mostyn said.
Bournemouth, currently 18th in their first Premier League season, have also announced that Hulsizer and Coppoletta will join their board of directors.
Russian owner Max Demin, who has played a crucial role in the club's rise to the top flight, remains involved.
In a statement, the club said Demin believes the new partnership will "further enable the club to deliver long-term success, providing strategic insight and international presence".
Peak6 failed in a takeover of Championship club Reading in the summer of 2014.
Bournemouth have been active in the US market for some time, forging links with Major League Soccer, including a pre-season friendly against Philadelphia Union earlier this year.
Eddie Howe's injury-ravaged squad has found life tough in the Premier League, and were beaten 1-0 by Newcastle on Saturday despite dominating the game for long periods.
Peak6's involvement could provide extra funds before the January transfer window.
"I am excited and honoured to partner with Maxim and AFC Bournemouth," Hulsizer told the club website.
"I was introduced to the club over two seasons ago and since then I have followed the club's progress and seen the tremendous accomplishments in that time.
"I am confident that we can establish ourselves in the top flight."