diff --git a/99.md b/99.md
index 724ce5f5..d137641d 100644
--- a/99.md
+++ b/99.md
@@ -8,7 +8,7 @@ Classified Listings
 
 This NIP defines `kind:30402`: an addressable event to describe classified listings that list any arbitrary product, service, or other thing for sale or offer and includes enough structured metadata to make them useful.
 
-The category of classifieds includes a very broad range of physical goods, services, work opportunities, rentals, free giveaways, personals, etc. and is distinct from the more strictly structured marketplaces defined in [NIP-15](15.md) that often sell many units of specific products through very specific channels.
+The specification supports a broad range of use cases physical goods, services, work opportunities, rentals, free giveaways, personals, etc. To promote interoperability between clients implementing NIP-99 for e-commerce, you can find the extension proposal [here](https://github.com/GammaMarkets/market-spec/blob/main/spec.md) which standardizes the e-commerce use case while maintaining the specification's lightweight and flexible nature. While [NIP-15](15.md) provides a strictly structured marketplace specification, NIP-99 has emerged as a simpler and more flexible alternative.
 
 The structure of these events is very similar to [NIP-23](23.md) long-form content events.