diff --git a/package-lock.json b/package-lock.json
index 97d9d68..8adc789 100644
--- a/package-lock.json
+++ b/package-lock.json
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@@ -4273,7 +4275,8 @@
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@@ -7639,7 +7642,8 @@
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@@ -7914,7 +7918,8 @@
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@@ -17892,7 +17897,8 @@
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diff --git a/package.json b/package.json
index 9fa0baf..8b9b19d 100644
--- a/package.json
+++ b/package.json
@@ -4,7 +4,7 @@
   "description": "An Ethereum Marketplace",
   "author": "gregory@dappuniversity.com",
   "dependencies": {
-    "@openzeppelin/contracts": "^2.5.0",
+    "@openzeppelin/contracts": "^4.7.2",
     "babel-polyfill": "6.26.0",
     "babel-preset-env": "1.7.0",
     "babel-preset-es2015": "6.24.1",