diff --git a/certora/specs/ERC1155.spec b/certora/specs/ERC1155.spec
index df8461f98..ee899b9d4 100644
--- a/certora/specs/ERC1155.spec
+++ b/certora/specs/ERC1155.spec
@@ -768,3 +768,111 @@ rule cantBurnBatchOtherBalances(env e){
                                 && otherBalanceBefore3 == otherBalanceAfter3)
                                 , "I like to see your money disappearing";
 }
+
+/////////////////////////////////////////////////
+// The rules below were added to this base ERC1155 spec as part of a later 
+// project with OpenZeppelin covering various ERC1155 extensions.
+/////////////////////////////////////////////////
+
+/// The result of transferring a single token must be equivalent whether done 
+/// via safeTransferFrom or safeBatchTransferFrom.
+rule singleTokenSafeTransferFromSafeBatchTransferFromEquivalence {
+    storage beforeTransfer = lastStorage;
+    env e;
+
+    address holder; address recipient;
+    uint256 token; uint256 transferAmount; bytes data;
+    uint256[] tokens; uint256[] transferAmounts;
+
+    mathint holderStartingBalance = balanceOf(holder, token);
+    mathint recipientStartingBalance = balanceOf(recipient, token);
+
+    require tokens.length == 1; require transferAmounts.length == 1;
+    require tokens[0] == token; require transferAmounts[0] == transferAmount;
+
+    // transferring via safeTransferFrom
+    safeTransferFrom(e, holder, recipient, token, transferAmount, data) at beforeTransfer;
+    mathint holderSafeTransferFromBalanceChange = holderStartingBalance - balanceOf(holder, token);
+    mathint recipientSafeTransferFromBalanceChange = balanceOf(recipient, token) - recipientStartingBalance;
+
+    // transferring via safeBatchTransferFrom
+    safeBatchTransferFrom(e, holder, recipient, tokens, transferAmounts, data) at beforeTransfer;
+    mathint holderSafeBatchTransferFromBalanceChange = holderStartingBalance - balanceOf(holder, token);
+    mathint recipientSafeBatchTransferFromBalanceChange = balanceOf(recipient, token) - recipientStartingBalance;
+
+    assert holderSafeTransferFromBalanceChange == holderSafeBatchTransferFromBalanceChange
+        && recipientSafeTransferFromBalanceChange == recipientSafeBatchTransferFromBalanceChange, 
+        "Transferring a single token via safeTransferFrom or safeBatchTransferFrom must be equivalent";
+}   
+
+/// The results of transferring multiple tokens must be equivalent whether done 
+/// separately via safeTransferFrom or together via safeBatchTransferFrom.
+rule multipleTokenSafeTransferFromSafeBatchTransferFromEquivalence {
+    storage beforeTransfers = lastStorage;
+    env e;
+
+    address holder; address recipient; bytes data;
+    uint256 tokenA; uint256 tokenB; uint256 tokenC;
+    uint256 transferAmountA; uint256 transferAmountB; uint256 transferAmountC;
+    uint256[] tokens; uint256[] transferAmounts;
+
+    mathint holderStartingBalanceA = balanceOf(holder, tokenA);
+    mathint holderStartingBalanceB = balanceOf(holder, tokenB);
+    mathint holderStartingBalanceC = balanceOf(holder, tokenC);
+    mathint recipientStartingBalanceA = balanceOf(recipient, tokenA);
+    mathint recipientStartingBalanceB = balanceOf(recipient, tokenB);
+    mathint recipientStartingBalanceC = balanceOf(recipient, tokenC);
+
+    require tokens.length == 3; require transferAmounts.length == 3;
+    require tokens[0] == tokenA; require transferAmounts[0] == transferAmountA;
+    require tokens[1] == tokenB; require transferAmounts[1] == transferAmountB;
+    require tokens[2] == tokenC; require transferAmounts[2] == transferAmountC;
+
+    // transferring via safeTransferFrom
+    safeTransferFrom(e, holder, recipient, tokenA, transferAmountA, data) at beforeTransfers;
+    safeTransferFrom(e, holder, recipient, tokenB, transferAmountB, data);
+    safeTransferFrom(e, holder, recipient, tokenC, transferAmountC, data);
+    mathint holderSafeTransferFromBalanceChangeA = holderStartingBalanceA - balanceOf(holder, tokenA);
+    mathint holderSafeTransferFromBalanceChangeB = holderStartingBalanceB - balanceOf(holder, tokenB);
+    mathint holderSafeTransferFromBalanceChangeC = holderStartingBalanceC - balanceOf(holder, tokenC);
+    mathint recipientSafeTransferFromBalanceChangeA = balanceOf(recipient, tokenA) - recipientStartingBalanceA;
+    mathint recipientSafeTransferFromBalanceChangeB = balanceOf(recipient, tokenB) - recipientStartingBalanceB;
+    mathint recipientSafeTransferFromBalanceChangeC = balanceOf(recipient, tokenC) - recipientStartingBalanceC;
+
+    // transferring via safeBatchTransferFrom
+    safeBatchTransferFrom(e, holder, recipient, tokens, transferAmounts, data) at beforeTransfers;
+    mathint holderSafeBatchTransferFromBalanceChangeA = holderStartingBalanceA - balanceOf(holder, tokenA);
+    mathint holderSafeBatchTransferFromBalanceChangeB = holderStartingBalanceB - balanceOf(holder, tokenB);
+    mathint holderSafeBatchTransferFromBalanceChangeC = holderStartingBalanceC - balanceOf(holder, tokenC);
+    mathint recipientSafeBatchTransferFromBalanceChangeA = balanceOf(recipient, tokenA) - recipientStartingBalanceA;
+    mathint recipientSafeBatchTransferFromBalanceChangeB = balanceOf(recipient, tokenB) - recipientStartingBalanceB;
+    mathint recipientSafeBatchTransferFromBalanceChangeC = balanceOf(recipient, tokenC) - recipientStartingBalanceC;
+
+    assert holderSafeTransferFromBalanceChangeA == holderSafeBatchTransferFromBalanceChangeA
+        && holderSafeTransferFromBalanceChangeB == holderSafeBatchTransferFromBalanceChangeB
+        && holderSafeTransferFromBalanceChangeC == holderSafeBatchTransferFromBalanceChangeC
+        && recipientSafeTransferFromBalanceChangeA == recipientSafeBatchTransferFromBalanceChangeA
+        && recipientSafeTransferFromBalanceChangeB == recipientSafeBatchTransferFromBalanceChangeB
+        && recipientSafeTransferFromBalanceChangeC == recipientSafeBatchTransferFromBalanceChangeC, 
+        "Transferring multiple tokens via safeTransferFrom or safeBatchTransferFrom must be equivalent";
+}
+
+/// If transfer methods do not revert, the input arrays must be the same length.
+rule transfersHaveSameLengthInputArrays {
+    env e;
+
+    address holder; address recipient; bytes data;
+    uint256[] tokens; uint256[] transferAmounts;
+    uint max_int = 0xffffffffffffffffffffffffffffffff;
+
+    require tokens.length >= 0 && tokens.length <= max_int;
+    require transferAmounts.length >= 0 && transferAmounts.length <= max_int;
+
+    safeBatchTransferFrom(e, holder, recipient, tokens, transferAmounts, data);
+
+    uint256 tokensLength = tokens.length;
+    uint256 transferAmountsLength = transferAmounts.length;
+
+    assert tokens.length == transferAmounts.length, 
+        "If transfer methods do not revert, the input arrays must be the same length";
+}
diff --git a/certora/specs/ERC1155Supply.spec b/certora/specs/ERC1155Supply.spec
index a843ff378..a33aaade6 100644
--- a/certora/specs/ERC1155Supply.spec
+++ b/certora/specs/ERC1155Supply.spec
@@ -28,109 +28,6 @@ filtered {
         "methods must not change the total supply of more than one token";
 }
 
-/// The result of transferring a single token must be equivalent whether done 
-/// via safeTransferFrom or safeBatchTransferFrom.
-rule singleTokenSafeTransferFromSafeBatchTransferFromEquivalence {
-    storage beforeTransfer = lastStorage;
-    env e;
-
-    address holder; address recipient;
-    uint256 token; uint256 transferAmount; bytes data;
-    uint256[] tokens; uint256[] transferAmounts;
-
-    mathint holderStartingBalance = balanceOf(holder, token);
-    mathint recipientStartingBalance = balanceOf(recipient, token);
-
-    require tokens.length == 1; require transferAmounts.length == 1;
-    require tokens[0] == token; require transferAmounts[0] == transferAmount;
-
-    // transferring via safeTransferFrom
-    safeTransferFrom(e, holder, recipient, token, transferAmount, data) at beforeTransfer;
-    mathint holderSafeTransferFromBalanceChange = holderStartingBalance - balanceOf(holder, token);
-    mathint recipientSafeTransferFromBalanceChange = balanceOf(recipient, token) - recipientStartingBalance;
-
-    // transferring via safeBatchTransferFrom
-    safeBatchTransferFrom(e, holder, recipient, tokens, transferAmounts, data) at beforeTransfer;
-    mathint holderSafeBatchTransferFromBalanceChange = holderStartingBalance - balanceOf(holder, token);
-    mathint recipientSafeBatchTransferFromBalanceChange = balanceOf(recipient, token) - recipientStartingBalance;
-
-    assert holderSafeTransferFromBalanceChange == holderSafeBatchTransferFromBalanceChange
-        && recipientSafeTransferFromBalanceChange == recipientSafeBatchTransferFromBalanceChange, 
-        "Transferring a single token via safeTransferFrom or safeBatchTransferFrom must be equivalent";
-}   
-
-/// The results of transferring multiple tokens must be equivalent whether done 
-/// separately via safeTransferFrom or together via safeBatchTransferFrom.
-rule multipleTokenSafeTransferFromSafeBatchTransferFromEquivalence {
-    storage beforeTransfers = lastStorage;
-    env e;
-
-    address holder; address recipient; bytes data;
-    uint256 tokenA; uint256 tokenB; uint256 tokenC;
-    uint256 transferAmountA; uint256 transferAmountB; uint256 transferAmountC;
-    uint256[] tokens; uint256[] transferAmounts;
-
-    mathint holderStartingBalanceA = balanceOf(holder, tokenA);
-    mathint holderStartingBalanceB = balanceOf(holder, tokenB);
-    mathint holderStartingBalanceC = balanceOf(holder, tokenC);
-    mathint recipientStartingBalanceA = balanceOf(recipient, tokenA);
-    mathint recipientStartingBalanceB = balanceOf(recipient, tokenB);
-    mathint recipientStartingBalanceC = balanceOf(recipient, tokenC);
-
-    require tokens.length == 3; require transferAmounts.length == 3;
-    require tokens[0] == tokenA; require transferAmounts[0] == transferAmountA;
-    require tokens[1] == tokenB; require transferAmounts[1] == transferAmountB;
-    require tokens[2] == tokenC; require transferAmounts[2] == transferAmountC;
-
-    // transferring via safeTransferFrom
-    safeTransferFrom(e, holder, recipient, tokenA, transferAmountA, data) at beforeTransfers;
-    safeTransferFrom(e, holder, recipient, tokenB, transferAmountB, data);
-    safeTransferFrom(e, holder, recipient, tokenC, transferAmountC, data);
-    mathint holderSafeTransferFromBalanceChangeA = holderStartingBalanceA - balanceOf(holder, tokenA);
-    mathint holderSafeTransferFromBalanceChangeB = holderStartingBalanceB - balanceOf(holder, tokenB);
-    mathint holderSafeTransferFromBalanceChangeC = holderStartingBalanceC - balanceOf(holder, tokenC);
-    mathint recipientSafeTransferFromBalanceChangeA = balanceOf(recipient, tokenA) - recipientStartingBalanceA;
-    mathint recipientSafeTransferFromBalanceChangeB = balanceOf(recipient, tokenB) - recipientStartingBalanceB;
-    mathint recipientSafeTransferFromBalanceChangeC = balanceOf(recipient, tokenC) - recipientStartingBalanceC;
-
-    // transferring via safeBatchTransferFrom
-    safeBatchTransferFrom(e, holder, recipient, tokens, transferAmounts, data) at beforeTransfers;
-    mathint holderSafeBatchTransferFromBalanceChangeA = holderStartingBalanceA - balanceOf(holder, tokenA);
-    mathint holderSafeBatchTransferFromBalanceChangeB = holderStartingBalanceB - balanceOf(holder, tokenB);
-    mathint holderSafeBatchTransferFromBalanceChangeC = holderStartingBalanceC - balanceOf(holder, tokenC);
-    mathint recipientSafeBatchTransferFromBalanceChangeA = balanceOf(recipient, tokenA) - recipientStartingBalanceA;
-    mathint recipientSafeBatchTransferFromBalanceChangeB = balanceOf(recipient, tokenB) - recipientStartingBalanceB;
-    mathint recipientSafeBatchTransferFromBalanceChangeC = balanceOf(recipient, tokenC) - recipientStartingBalanceC;
-
-    assert holderSafeTransferFromBalanceChangeA == holderSafeBatchTransferFromBalanceChangeA
-        && holderSafeTransferFromBalanceChangeB == holderSafeBatchTransferFromBalanceChangeB
-        && holderSafeTransferFromBalanceChangeC == holderSafeBatchTransferFromBalanceChangeC
-        && recipientSafeTransferFromBalanceChangeA == recipientSafeBatchTransferFromBalanceChangeA
-        && recipientSafeTransferFromBalanceChangeB == recipientSafeBatchTransferFromBalanceChangeB
-        && recipientSafeTransferFromBalanceChangeC == recipientSafeBatchTransferFromBalanceChangeC, 
-        "Transferring multiple tokens via safeTransferFrom or safeBatchTransferFrom must be equivalent";
-}
-
-/// If transfer methods do not revert, the input arrays must be the same length.
-rule transfersHaveSameLengthInputArrays {
-    env e;
-
-    address holder; address recipient; bytes data;
-    uint256[] tokens; uint256[] transferAmounts;
-    uint max_int = 0xffffffffffffffffffffffffffffffff;
-
-    require tokens.length >= 0 && tokens.length <= max_int;
-    require transferAmounts.length >= 0 && transferAmounts.length <= max_int;
-
-    safeBatchTransferFrom(e, holder, recipient, tokens, transferAmounts, data);
-
-    uint256 tokensLength = tokens.length;
-    uint256 transferAmountsLength = transferAmounts.length;
-
-    assert tokens.length == transferAmounts.length, 
-        "If transfer methods do not revert, the input arrays must be the same length";
-}
-
 /******************************************************************************/
 
 ghost mapping(uint256 => mathint) sumOfBalances {