diff --git a/dev-docs/bidders/gumgum.md b/dev-docs/bidders/gumgum.md
index 946e87230c..b3427cf8b4 100644
--- a/dev-docs/bidders/gumgum.md
+++ b/dev-docs/bidders/gumgum.md
@@ -33,6 +33,7 @@ Client side and server side parameters differ slightly. For Server side (Prebid
 | `zone`         | required for all bid requests tracking a single domain or site   | Tracking ID           | `'ggumtest'`           | `string`  |
 | `pubId`        | required for all bid requests tracking multiple domains or sites | Publisher ID          | `123`                  | `integer` |
 | `irisid`       | optional                                                         | Iris.tv ID            | `'iris_6f9285823a4'`   | `string`  |
+| `slot`         | optional                                                         | Placement ID          | `40`                   | `number`  |
 
 ### Client Side Bid Params