SPIE Bylaws (as amended 14 November 2023) by the Board of Directors) for the regulation, except as otherwise provided by statutes or its Articles of Incorporation of The Society of Photo-Optical Instrumentation Engineers, also known as "SPIE" (a California nonprofit corporation).
A pdf of the SPIE Bylaws can be downloaded here
If you have questions regarding the SPIE bylaws email governance@spie.org