BLUF - if it is needed as a contract requirement, it must be IN the contract. If it is not in the contract, the standards generally can’t be enforced.

From https://www.sae.org/standards/content/as9115a/

• this standard supplements the 9100 standard requirements for deliverable software and contains quality management system requirements for organizations that design, develop, and/or produce deliverable software and services for the aviation, space, and defense industry.
• the organization and customer, and/or supplier shall agree on the extent of applicability of this supplement.

FAR 52.246-11 Higher-Level Contract Quality Requirement provides the ability to tailor the standard (Contracting Officer insert the title, number (if any), date, and tailoring (if any) of the higher-level quality standards.)

Whether the requirements of AS9115 should be included would be based on based on a review of the technical data package, ESA requirement, criticality and complexity of the item, or history of quality deficiencies. The AS9100 standard must be in the contract in order to include AS9115 as it is not a stand-alone standard. But having AS9100 does not include the (supplemental) requirements of AS9115. FAR 46.202-4 is NOT an all-encompassing list, but examples which is further emphasized by the use of “such as”.

Please consult with the requiring activity, contracting, SAE, and contractor (as appropriate) to determine whether the inclusion of the requirements of AS9115 is needed and path forward.