If a business partner is excluded from major decisions about the company's operations, finances, policies, or other managing issues typically requiring co-approval, they may be able to legally compel their involvement.
Options include filing for an injunction to require joint decision-making or suing for breach of fiduciary duty if the managing partner is acting negligently or self-serving without regard for the other's rights and interests. Renegotiating the partnership agreement is best, but legal action may be needed if attempted resolutions remain unsuccessful.