diff --git a/.circleci/config.yml b/.circleci/config.yml
index 3716d9744..e4d32a9e3 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -225,7 +225,7 @@ jobs:
       - run:
           name: Install check_contract
           # Uses --debug for compilation speed
-          command: cargo install --debug --version 1.1.0 --features iterator --example check_contract --locked -- cosmwasm-vm
+          command: cargo install --debug --version 1.1.0 --locked -- cosmwasm-check
       - save_cache:
           paths:
             - /usr/local/cargo/registry
@@ -233,12 +233,7 @@ jobs:
           key: cargocache-wasm-rust:1.60.0-{{ checksum "~/project/Cargo.lock" }}
       - run:
           name: Check wasm contracts
-          command: |
-            for W in ./target/wasm32-unknown-unknown/release/*.wasm
-            do
-              echo -n "Checking `basename $W`... "
-              check_contract $W
-            done
+          command: cosmwasm-check ./target/wasm32-unknown-unknown/release/*.wasm
 
   # This job roughly follows the instructions from https://circleci.com/blog/publishing-to-github-releases-via-circleci/
   build_and_upload_contracts:
diff --git a/Cargo.lock b/Cargo.lock
index 976af4557..d88bcae6c 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4,9 +4,9 @@ version = 3
 
 [[package]]
 name = "anyhow"
-version = "1.0.64"
+version = "1.0.65"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b9a8f622bcf6ff3df478e9deba3e03e4e04b300f8e6a139e192c05fa3490afc7"
+checksum = "98161a4e3e2184da77bb14f02184cdd111e83bbbcc9979dfee3c44b9a85f5602"
 
 [[package]]
 name = "base16ct"
@@ -184,9 +184,9 @@ dependencies = [
 
 [[package]]
 name = "cw-storage-plus"
-version = "0.14.0"
+version = "0.15.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1c8b264257c4f44c49b7ce09377af63aa040768ecd3fd7bdd2d48a09323a1e90"
+checksum = "39ba3fb5fad2dce94263d070848b2befc46b5c8e4929adfb9a3595267823d6ec"
 dependencies = [
  "cosmwasm-std",
  "schemars",
@@ -195,10 +195,11 @@ dependencies = [
 
 [[package]]
 name = "cw-utils"
-version = "0.14.0"
+version = "0.15.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "414b91f3d7a619bb26c835119d7095804596a1382ddc1d184c33c1d2c17f6c5e"
+checksum = "7a67007ff056f4cd034f361c8ed69780c0180959b9c8037c84f3caa78120faf5"
 dependencies = [
+ "cosmwasm-schema",
  "cosmwasm-std",
  "cw2",
  "schemars",
@@ -209,10 +210,11 @@ dependencies = [
 
 [[package]]
 name = "cw2"
-version = "0.14.0"
+version = "0.15.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "aa74c324af8e3506fd8d50759a265bead3f87402e413c840042af5d2808463d6"
+checksum = "b0a1924a28607bf7cb9fd6681a64feea3e5fa9a8cb71fb4d24cf33635b21065a"
 dependencies = [
+ "cosmwasm-schema",
  "cosmwasm-std",
  "cw-storage-plus",
  "schemars",
@@ -221,10 +223,11 @@ dependencies = [
 
 [[package]]
 name = "cw20"
-version = "0.14.0"
+version = "0.15.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4f446f59c519fbac5ab8b9f6c7f8dcaa05ee761703971406b28221ea778bb737"
+checksum = "56a48e4a85c0a31484e053a3eea15abfc3ed24fafc1a1a3e91181a0bd3a8ee91"
 dependencies = [
+ "cosmwasm-schema",
  "cosmwasm-std",
  "cw-utils",
  "schemars",
@@ -233,7 +236,7 @@ dependencies = [
 
 [[package]]
 name = "cw2981-royalties"
-version = "0.14.0"
+version = "0.15.0"
 dependencies = [
  "cosmwasm-schema",
  "cosmwasm-std",
@@ -244,9 +247,22 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "cw3"
+version = "0.15.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "961f6959e04de1bc61f4fc3f333bc039998e2aedeab4aa79ba48239cf2d3edfa"
+dependencies = [
+ "cosmwasm-schema",
+ "cosmwasm-std",
+ "cw-utils",
+ "schemars",
+ "serde",
+]
+
 [[package]]
 name = "cw721"
-version = "0.14.0"
+version = "0.15.0"
 dependencies = [
  "cosmwasm-schema",
  "cosmwasm-std",
@@ -257,7 +273,7 @@ dependencies = [
 
 [[package]]
 name = "cw721-base"
-version = "0.14.0"
+version = "0.15.0"
 dependencies = [
  "cosmwasm-schema",
  "cosmwasm-std",
@@ -272,7 +288,7 @@ dependencies = [
 
 [[package]]
 name = "cw721-fixed-price"
-version = "0.14.0"
+version = "0.15.0"
 dependencies = [
  "cosmwasm-schema",
  "cosmwasm-std",
@@ -280,6 +296,7 @@ dependencies = [
  "cw-utils",
  "cw2",
  "cw20",
+ "cw3",
  "cw721-base",
  "prost",
  "schemars",
@@ -289,7 +306,7 @@ dependencies = [
 
 [[package]]
 name = "cw721-metadata-onchain"
-version = "0.14.0"
+version = "0.15.0"
 dependencies = [
  "cosmwasm-schema",
  "cosmwasm-std",
@@ -476,9 +493,9 @@ dependencies = [
 
 [[package]]
 name = "itertools"
-version = "0.10.3"
+version = "0.10.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a9a9d19fa1e79b6215ff29b9d6880b706147f16e9b1dbb1e4e5947b5b02bc5e3"
+checksum = "d8bf247779e67a9082a4790b45e71ac7cfd1321331a5c856a74a9faebdab78d0"
 dependencies = [
  "either",
 ]
@@ -491,9 +508,9 @@ checksum = "6c8af84674fe1f223a982c933a0ee1086ac4d4052aa0fb8060c12c6ad838e754"
 
 [[package]]
 name = "k256"
-version = "0.11.4"
+version = "0.11.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6db2573d3fd3e4cc741affc9b5ce1a8ce36cf29f09f80f36da4309d0ae6d7854"
+checksum = "3636d281d46c3b64182eb3a0a42b7b483191a2ecc3f05301fa67403f7c9bc949"
 dependencies = [
  "cfg-if",
  "ecdsa",
@@ -763,18 +780,18 @@ dependencies = [
 
 [[package]]
 name = "thiserror"
-version = "1.0.34"
+version = "1.0.35"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8c1b05ca9d106ba7d2e31a9dab4a64e7be2cce415321966ea3132c49a656e252"
+checksum = "c53f98874615aea268107765aa1ed8f6116782501d18e53d08b471733bea6c85"
 dependencies = [
  "thiserror-impl",
 ]
 
 [[package]]
 name = "thiserror-impl"
-version = "1.0.34"
+version = "1.0.35"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e8f2591983642de85c921015f3f070c665a197ed69e417af436115e3a1407487"
+checksum = "f8b463991b4eab2d801e724172285ec4195c650e8ec79b149e6c2a8e6dd3f783"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -801,9 +818,9 @@ dependencies = [
 
 [[package]]
 name = "unicode-ident"
-version = "1.0.3"
+version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c4f5b37a154999a8f3f98cc23a628d850e154479cd94decf3414696e12e31aaf"
+checksum = "dcc811dc4066ac62f84f11307873c4850cb653bfa9b1719cee2bd2204a4bc5dd"
 
 [[package]]
 name = "version_check"
diff --git a/contracts/cw2981-royalties/Cargo.toml b/contracts/cw2981-royalties/Cargo.toml
index 7467bd037..9c81f4eec 100644
--- a/contracts/cw2981-royalties/Cargo.toml
+++ b/contracts/cw2981-royalties/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "cw2981-royalties"
-version = "0.14.0"
+version = "0.15.0"
 authors = ["Alex Lynham <alex@lynh.am>"]
 edition = "2021"
 description = "Basic implementation of royalties for cw721 NFTs with token level royalties"
@@ -27,8 +27,10 @@ library = []
 [dependencies]
 cosmwasm-schema = "1.1.0"
 cosmwasm-std = "1.1.0"
-cw2 = "0.14.0"
-cw721 = { path = "../../packages/cw721" }
-cw721-base = { path = "../cw721-base", features = ["library"] }
+cw2 = "0.15.0"
+cw721 = { path = "../../packages/cw721", version = "0.15.0" }
+cw721-base = { path = "../cw721-base", version = "0.15.0", features = [
+  "library",
+] }
 schemars = "0.8.10"
 serde = { version = "1.0.140", default-features = false, features = ["derive"] }
diff --git a/contracts/cw721-base/Cargo.toml b/contracts/cw721-base/Cargo.toml
index 42e084fe2..b2fbe8976 100644
--- a/contracts/cw721-base/Cargo.toml
+++ b/contracts/cw721-base/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "cw721-base"
-version = "0.14.0"
+version = "0.15.0"
 authors = [
   "Ethan Frey <ethanfrey@users.noreply.github.com>",
   "Orkun Külçe <orkun@deuslabs.fi>",
@@ -30,10 +30,10 @@ library = []
 [dependencies]
 cosmwasm-schema = "1.1.0"
 cosmwasm-std = "1.1.0"
-cw2 = "0.14.0"
-cw721 = { path = "../../packages/cw721" }
-cw-storage-plus = "0.14.0"
-cw-utils = "0.14.0"
+cw-utils = "0.15.0"
+cw2 = "0.15.0"
+cw721 = { path = "../../packages/cw721", version = "0.15.0" }
+cw-storage-plus = "0.15.0"
 schemars = "0.8.10"
 serde = { version = "1.0.140", default-features = false, features = ["derive"] }
 thiserror = "1.0.31"
diff --git a/contracts/cw721-base/schema/all_nft_info_response.json b/contracts/cw721-base/schema/all_nft_info_response.json
index eb23abb52..d263321e2 100644
--- a/contracts/cw721-base/schema/all_nft_info_response.json
+++ b/contracts/cw721-base/schema/all_nft_info_response.json
@@ -91,7 +91,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/contracts/cw721-base/schema/approval_response.json b/contracts/cw721-base/schema/approval_response.json
index 21816dedc..b29eab59e 100644
--- a/contracts/cw721-base/schema/approval_response.json
+++ b/contracts/cw721-base/schema/approval_response.json
@@ -73,7 +73,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/contracts/cw721-base/schema/approvals_response.json b/contracts/cw721-base/schema/approvals_response.json
index 701cb083d..7cdac0015 100644
--- a/contracts/cw721-base/schema/approvals_response.json
+++ b/contracts/cw721-base/schema/approvals_response.json
@@ -76,7 +76,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/contracts/cw721-base/schema/execute_msg.json b/contracts/cw721-base/schema/execute_msg.json
index ca78751b5..858e2bc09 100644
--- a/contracts/cw721-base/schema/execute_msg.json
+++ b/contracts/cw721-base/schema/execute_msg.json
@@ -281,7 +281,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/contracts/cw721-base/schema/operators_response.json b/contracts/cw721-base/schema/operators_response.json
index 14c0e2265..533a096dd 100644
--- a/contracts/cw721-base/schema/operators_response.json
+++ b/contracts/cw721-base/schema/operators_response.json
@@ -76,7 +76,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/contracts/cw721-base/schema/owner_of_response.json b/contracts/cw721-base/schema/owner_of_response.json
index 5c82729d5..abb9006d8 100644
--- a/contracts/cw721-base/schema/owner_of_response.json
+++ b/contracts/cw721-base/schema/owner_of_response.json
@@ -82,7 +82,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/contracts/cw721-base/src/state.rs b/contracts/cw721-base/src/state.rs
index 8c23a4f9d..fe1f3bd46 100644
--- a/contracts/cw721-base/src/state.rs
+++ b/contracts/cw721-base/src/state.rs
@@ -147,6 +147,6 @@ where
     }
 }
 
-pub fn token_owner_idx<T>(d: &TokenInfo<T>) -> Addr {
+pub fn token_owner_idx<T>(_pk: &[u8], d: &TokenInfo<T>) -> Addr {
     d.owner.clone()
 }
diff --git a/contracts/cw721-fixed-price/Cargo.toml b/contracts/cw721-fixed-price/Cargo.toml
index 3ce5e1129..5342dd564 100644
--- a/contracts/cw721-fixed-price/Cargo.toml
+++ b/contracts/cw721-fixed-price/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "cw721-fixed-price"
-version = "0.14.0"
+version = "0.15.0"
 authors = ["Vernon Johnson <vtj2105@columbia.edu>"]
 edition = "2021"
 
@@ -42,14 +42,18 @@ optimize = """docker run --rm -v "$(pwd)":/code \
 [dependencies]
 cosmwasm-schema = "1.1.0"
 cosmwasm-std = "1.1.0"
-cw2 = "0.14.0"
-cw721-base = { path = "../cw721-base", features = ["library"] }
-cw-storage-plus = "0.14.0"
-cw-utils = "0.14.0"
-cw20 = "0.14.0"
+cw-storage-plus = "0.15.0"
+cw2 = "0.15.0"
 schemars = "0.8.10"
+cw721-base = { path = "../cw721-base", version = "0.15.0", features = [
+  "library",
+] }
+cw20 = "0.15.0"
 serde = { version = "1.0.140", default-features = false, features = ["derive"] }
-thiserror = "1.0.31"
+thiserror = { version = "1.0.31" }
+cw-utils = "0.15.0"
+prost = "0.10.4"
+cw3 = "0.15.0"
 
 [dev-dependencies]
 prost = "0.10"
diff --git a/contracts/cw721-fixed-price/schema/execute_msg.json b/contracts/cw721-fixed-price/schema/execute_msg.json
index dc39f5520..08d874b4e 100644
--- a/contracts/cw721-fixed-price/schema/execute_msg.json
+++ b/contracts/cw721-fixed-price/schema/execute_msg.json
@@ -38,7 +38,8 @@
         "sender": {
           "type": "string"
         }
-      }
+      },
+      "additionalProperties": false
     },
     "Uint128": {
       "description": "A thin wrapper around u128 that is using strings for JSON encoding/decoding, such that the full u128 range can be used for clients that convert JSON numbers to floats, like JavaScript and jq.\n\n# Examples\n\nUse `from` to create instances of this and `u128` to get the value out:\n\n``` # use cosmwasm_std::Uint128; let a = Uint128::from(123u128); assert_eq!(a.u128(), 123);\n\nlet b = Uint128::from(42u64); assert_eq!(b.u128(), 42);\n\nlet c = Uint128::from(70u32); assert_eq!(c.u128(), 70); ```",
diff --git a/contracts/cw721-metadata-onchain/Cargo.toml b/contracts/cw721-metadata-onchain/Cargo.toml
index 2f0eb084c..051c7f61a 100644
--- a/contracts/cw721-metadata-onchain/Cargo.toml
+++ b/contracts/cw721-metadata-onchain/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "cw721-metadata-onchain"
-version = "0.14.0"
+version = "0.15.0"
 authors = [
   "Ethan Frey <ethanfrey@users.noreply.github.com>",
   "Orkun Külçe <orkun@deuslabs.fi>",
@@ -30,8 +30,10 @@ library = []
 [dependencies]
 cosmwasm-schema = "1.1.0"
 cosmwasm-std = "1.1.0"
-cw2 = "0.14.0"
-cw721 = { path = "../../packages/cw721" }
-cw721-base = { path = "../cw721-base", features = ["library"] }
+cw2 = "0.15.0"
+cw721 = { path = "../../packages/cw721", version = "0.15.0" }
+cw721-base = { path = "../cw721-base", version = "0.15.0", features = [
+  "library",
+] }
 schemars = "0.8.10"
 serde = { version = "1.0.140", default-features = false, features = ["derive"] }
diff --git a/contracts/cw721-metadata-onchain/schema/all_nft_info_response.json b/contracts/cw721-metadata-onchain/schema/all_nft_info_response.json
index c4a3ad0f3..843e1da3e 100644
--- a/contracts/cw721-metadata-onchain/schema/all_nft_info_response.json
+++ b/contracts/cw721-metadata-onchain/schema/all_nft_info_response.json
@@ -87,7 +87,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/contracts/cw721-metadata-onchain/schema/approval_response.json b/contracts/cw721-metadata-onchain/schema/approval_response.json
index 21816dedc..b29eab59e 100644
--- a/contracts/cw721-metadata-onchain/schema/approval_response.json
+++ b/contracts/cw721-metadata-onchain/schema/approval_response.json
@@ -73,7 +73,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/contracts/cw721-metadata-onchain/schema/approvals_response.json b/contracts/cw721-metadata-onchain/schema/approvals_response.json
index 701cb083d..7cdac0015 100644
--- a/contracts/cw721-metadata-onchain/schema/approvals_response.json
+++ b/contracts/cw721-metadata-onchain/schema/approvals_response.json
@@ -76,7 +76,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/contracts/cw721-metadata-onchain/schema/execute_msg.json b/contracts/cw721-metadata-onchain/schema/execute_msg.json
index b36382022..30b2da5f6 100644
--- a/contracts/cw721-metadata-onchain/schema/execute_msg.json
+++ b/contracts/cw721-metadata-onchain/schema/execute_msg.json
@@ -281,7 +281,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/contracts/cw721-metadata-onchain/schema/operators_response.json b/contracts/cw721-metadata-onchain/schema/operators_response.json
index 14c0e2265..533a096dd 100644
--- a/contracts/cw721-metadata-onchain/schema/operators_response.json
+++ b/contracts/cw721-metadata-onchain/schema/operators_response.json
@@ -76,7 +76,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/contracts/cw721-metadata-onchain/schema/owner_of_response.json b/contracts/cw721-metadata-onchain/schema/owner_of_response.json
index 5c82729d5..abb9006d8 100644
--- a/contracts/cw721-metadata-onchain/schema/owner_of_response.json
+++ b/contracts/cw721-metadata-onchain/schema/owner_of_response.json
@@ -82,7 +82,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/packages/cw721/Cargo.toml b/packages/cw721/Cargo.toml
index 2d6ed3655..a2dfa00c8 100644
--- a/packages/cw721/Cargo.toml
+++ b/packages/cw721/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "cw721"
-version = "0.14.0"
+version = "0.15.0"
 authors = [
     "Ethan Frey <ethanfrey@users.noreply.github.com>",
     "Orkun Külçe <orkun@deuslabs.fi>",
@@ -15,6 +15,6 @@ documentation = "https://docs.cosmwasm.com"
 [dependencies]
 cosmwasm-schema = "1.1.0"
 cosmwasm-std = "1.1.0"
-cw-utils = "0.14.0"
+cw-utils = "0.15.0"
 schemars = "0.8.10"
 serde = { version = "1.0.140", default-features = false, features = ["derive"] }
diff --git a/packages/cw721/schema/all_nft_info_response.json b/packages/cw721/schema/all_nft_info_response.json
index eb23abb52..d263321e2 100644
--- a/packages/cw721/schema/all_nft_info_response.json
+++ b/packages/cw721/schema/all_nft_info_response.json
@@ -91,7 +91,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/packages/cw721/schema/approval_response.json b/packages/cw721/schema/approval_response.json
index 21816dedc..b29eab59e 100644
--- a/packages/cw721/schema/approval_response.json
+++ b/packages/cw721/schema/approval_response.json
@@ -73,7 +73,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/packages/cw721/schema/approvals_response.json b/packages/cw721/schema/approvals_response.json
index 701cb083d..7cdac0015 100644
--- a/packages/cw721/schema/approvals_response.json
+++ b/packages/cw721/schema/approvals_response.json
@@ -76,7 +76,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/packages/cw721/schema/cw721_execute_msg.json b/packages/cw721/schema/cw721_execute_msg.json
index d2b91ed18..eb09359fb 100644
--- a/packages/cw721/schema/cw721_execute_msg.json
+++ b/packages/cw721/schema/cw721_execute_msg.json
@@ -241,7 +241,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/packages/cw721/schema/operators_response.json b/packages/cw721/schema/operators_response.json
index 14c0e2265..533a096dd 100644
--- a/packages/cw721/schema/operators_response.json
+++ b/packages/cw721/schema/operators_response.json
@@ -76,7 +76,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false
diff --git a/packages/cw721/schema/owner_of_response.json b/packages/cw721/schema/owner_of_response.json
index 5c82729d5..abb9006d8 100644
--- a/packages/cw721/schema/owner_of_response.json
+++ b/packages/cw721/schema/owner_of_response.json
@@ -82,7 +82,8 @@
           ],
           "properties": {
             "never": {
-              "type": "object"
+              "type": "object",
+              "additionalProperties": false
             }
           },
           "additionalProperties": false