diff --git a/services/contract_create.proto b/services/contract_create.proto
index e091f001..e5503368 100644
--- a/services/contract_create.proto
+++ b/services/contract_create.proto
@@ -167,8 +167,12 @@ message ContractCreateTransactionBody {
     string memo = 13;
 
     /**
-     * The maximum number of tokens that this contract can be automatically associated
-     * with (i.e., receive air-drops from).
+     * The maximum number of tokens that can be auto-associated with the contract.<br/>
+     * If this is less than or equal to `used_auto_associations`, or 0, then this contract
+     * MUST manually associate with a token before transacting in that token.<br/>
+     * This value MAY also be `-1` to indicate no limit.<br/>
+     * This value MUST NOT be less than `-1`.<br/>
+     * By default this value is 0 for contracts.
      */
     int32 max_automatic_token_associations = 14;
 
diff --git a/services/contract_update.proto b/services/contract_update.proto
index 559fbdc0..cc8b714a 100644
--- a/services/contract_update.proto
+++ b/services/contract_update.proto
@@ -99,8 +99,12 @@ message ContractUpdateTransactionBody {
     }
 
     /**
-     * If set, the new maximum number of tokens that this contract can be 
-     * automatically associated with (i.e., receive air-drops from).
+     * If set, modify the maximum number of tokens that can be auto-associated with the
+     * contract.<br/>
+     * If this is set and less than or equal to `used_auto_associations`, or 0, then this contract
+     * MUST manually associate with a token before transacting in that token.<br/>
+     * This value MAY also be `-1` to indicate no limit.<br/>
+     * This value MUST NOT be less than `-1`.
      */
     google.protobuf.Int32Value max_automatic_token_associations = 11;