3GPP 24.501 v20.0.0 — the document's own text
8.2.7.42 Negotiated PEIPS assistance information
Taught in 4. Inside TS 24.501, the document at the centre (CT1 — the group that writes what your phone says, overview).
The network shall include the Negotiated PEIPS assistance information IE if the network needs to provide the PEIPS assistance information to the UE.