diff --git a/go.mod b/go.mod
index 15d092de1..746d86496 100644
--- a/go.mod
+++ b/go.mod
@@ -8,7 +8,7 @@ require (
 	github.com/cosmos/go-bip39 v0.0.0-20180819234021-555e2067c45d
 	github.com/cosmos/ledger-cosmos-go v0.11.1
 	github.com/gogo/protobuf v1.3.1
-	github.com/golang/mock v1.4.1
+	github.com/golang/mock v1.4.2
 	github.com/golang/protobuf v1.3.5
 	github.com/gorilla/handlers v1.4.2
 	github.com/gorilla/mux v1.7.4
diff --git a/go.sum b/go.sum
index 0b88b0f01..27c8f005d 100644
--- a/go.sum
+++ b/go.sum
@@ -133,8 +133,8 @@ github.com/golang/groupcache v0.0.0-20160516000752-02826c3e7903/go.mod h1:cIg4er
 github.com/golang/groupcache v0.0.0-20190129154638-5b532d6fd5ef/go.mod h1:cIg4eruTrX1D+g88fzRXU5OdNfaM+9IcxsU14FzY7Hc=
 github.com/golang/groupcache v0.0.0-20190702054246-869f871628b6/go.mod h1:cIg4eruTrX1D+g88fzRXU5OdNfaM+9IcxsU14FzY7Hc=
 github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
-github.com/golang/mock v1.4.1 h1:ocYkMQY5RrXTYgXl7ICpV0IXwlEQGwKIsery4gyXa1U=
-github.com/golang/mock v1.4.1/go.mod h1:UOMv5ysSaYNkG+OFQykRIcU/QvvxJf3p21QfJ2Bt3cw=
+github.com/golang/mock v1.4.2 h1:fXIkPzOBCwDUPvYmOPzETABgbqpYlYNigQ2o64eMr5c=
+github.com/golang/mock v1.4.2/go.mod h1:UOMv5ysSaYNkG+OFQykRIcU/QvvxJf3p21QfJ2Bt3cw=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.3.0/go.mod h1:Qd/q+1AKNOZr9uGQzbzCmRO6sUih6GTPZv6a1/R87v0=
 github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
diff --git a/x/distribution/spec/07_params.md b/x/distribution/spec/07_params.md
index 5a933e923..2bcefd0c3 100644
--- a/x/distribution/spec/07_params.md
+++ b/x/distribution/spec/07_params.md
@@ -6,9 +6,13 @@ order: 7
 
 The distribution module contains the following parameters:
 
-| Key                 | Type         | Example                |
-|---------------------|--------------|------------------------|
-| communitytax        | string (dec) | "0.020000000000000000" |
-| baseproposerreward  | string (dec) | "0.010000000000000000" |
-| bonusproposerreward | string (dec) | "0.040000000000000000" |
-| withdrawaddrenabled | bool         | true                   |
+| Key                 | Type         | Example                    |
+| ------------------- | ------------ | -------------------------- |
+| communitytax        | string (dec) | "0.020000000000000000" [0] |
+| baseproposerreward  | string (dec) | "0.010000000000000000" [1] |
+| bonusproposerreward | string (dec) | "0.040000000000000000" [1] |
+| withdrawaddrenabled | bool         | true                       |
+
+* [0] The value of `communitytax` must be positive and cannot exceed 1%.
+* [1] The sum of `baseproposerreward` and `bonusproposerreward` cannot exceed 1%.
+Both values must be positive.