Ohio Rev. Code Ann. § 1706.18

No person shall have the power to bind the limited liability company, or a series thereof, except:

(A) To the extent the person is authorized to act as the agent of the limited liability company or a series thereof under or pursuant to the operating agreement;

(B) To the extent the person is authorized to act as the agent of the limited liability company or a series thereof pursuant to division (A) of section 1706.30 of the Revised Code;

(C) To the extent provided in section 1706.19 of the Revised Code;

(D) To the extent provided by law other than this chapter.