Red Bull F1 boss Christian Horner will face a hearing on Friday over a complaint of inappropriate behaviour.
Red Bull's wider company launched the investigation and said on Monday in a statement it is taking the allegation and investigation "extremely seriously."
The statement read: "After being made aware of certain recent allegations, the company launched an independent investigation. This process, which is already under way, is being carried out by an external specialist barrister. The company takes these matters extremely seriously and the investigation will be completed as soon as practically possible. It would not be appropriate to comment further at this time."
A spokesperson for Horner, 50, said he "rejects these claims entirely", although the F1 team did not comment further.
Sources say the allegation is around controlling text messages and behaviour towards one employee of Red Bull's F1 team, although the company has not officially clarified.
Horner, 50, has not been suspended and is expected to work as normal at the team's Milton Keynes headquarters until the hearing takes place.
Horner has been in charge of the team since its inception in 2005. Under his guidance, Red Bull has won six constructors' championships and seven drivers' championships, three of which have come consecutively with Max Verstappen since 2021.
Red Bull comes into the new season off the back of the most dominant season in history, which saw the team win 21 of the 22 races.
F1's new season starts with the Bahrain Grand Prix on March 2.