diff --git a/ext/misc/decimal.c b/ext/misc/decimal.c
index 1a1abdab87..39f6836f3b 100644
--- a/ext/misc/decimal.c
+++ b/ext/misc/decimal.c
@@ -411,7 +411,7 @@ static void decimal_result_sci(sqlite3_context *pCtx, Decimal *p, int N){
 **    pB->isNull==0
 */
 static int decimal_cmp(Decimal *pA, Decimal *pB){
-  int nASig, nBSig, rc, n;
+  int nASig, nBSig, rc, n, iA, iB;
   while( pA->nFrac>0 && pA->a[pA->nDigit-1]==0 ){
     pA->nDigit--;
     pA->nFrac--;
@@ -428,16 +428,18 @@ static int decimal_cmp(Decimal *pA, Decimal *pB){
     pA = pB;
     pB = pTemp;
   }
-  nASig = pA->nDigit - pA->nFrac;
-  nBSig = pB->nDigit - pB->nFrac;
+  for(iA=0; iA<pA->nDigit-pA->nFrac && pA->a[iA]==0; iA++){}
+  for(iB=0; iB<pB->nDigit-pB->nFrac && pB->a[iB]==0; iB++){}
+  nASig = pA->nDigit - pA->nFrac - iA;
+  nBSig = pB->nDigit - pB->nFrac - iB;
   if( nASig!=nBSig ){
     return nASig - nBSig;
   }
-  n = pA->nDigit;
-  if( n>pB->nDigit ) n = pB->nDigit;
-  rc = memcmp(pA->a, pB->a, n);
+  n = pA->nDigit - iA;
+  if( n>pB->nDigit - iB ) n = pB->nDigit - iB;
+  rc = memcmp(pA->a+iA, pB->a+iB, n);
   if( rc==0 ){
-    rc = pA->nDigit - pB->nDigit;
+    rc = (pA->nDigit - iA) - (pB->nDigit - iB);
   }
   return rc;
 }
diff --git a/manifest b/manifest
index 92530335fd..4a57d8cf7b 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Merge\sthe\slatest\sbranch-3.54\sfixes\sonto\strunk
-D 2026-10-19T18:26:06.211
+C Fix\serrors\sin\sthe\sdecimal_cmp()\scomparison\sroutine\sof\sthe\sdecimal\sextension,\nand\sthe\scorresponding\s"decimal"\scollating\ssequence,\sas\sreported\sby\n[bugs:/info/2026-10-19T06:35:26Z|Bug\s2026-10-19T06:35:26Z]
+D 2026-10-19T23:22:16.673
 F .fossil-settings/binary-glob 61195414528fb3ea9693577e1980230d78a1f8b0a54c78cf1b9b24d0a409ed6a x
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
@@ -375,7 +375,7 @@ F ext/misc/completion.c 3f5db28e88c3313103b2dd86d910a2944fd500c46754e473493968ce
 F ext/misc/compress.c c4597f0e3c63a5f89af55486490f9d69896b0482898f2ddb8a46aa11e4d13016
 F ext/misc/csv.c 5ca451b9ce77322c4ce8476766e7ed18160e5c8b19e7cab76e13006d631b9e8f
 F ext/misc/dbdump.c 678f1b9ae2317b4473f65d03132a2482c3f4b08920799ed80feedd2941a06680
-F ext/misc/decimal.c ad9aca50c2bc582489c22c56edc331fae3dfccc2f9043c4f4311f97678ea65a1
+F ext/misc/decimal.c 68e987966e4772efdb8df03e2bf253d02bae3254af29fd4a99d34fc6e6f3e2f9
 F ext/misc/diskused.c 444139c01398df6f73e8a021c91e24d97d7914f5c1b49f55dd503abbca347c6e
 F ext/misc/eval.c d4ea2d9898fbe4d30d38ff675ee51958d3bb0601a145bade56dee8b8f438cc5b
 F ext/misc/explain.c 04c9270fd8cf93a9bceb12d2f5f67e3f09a4e58b3e0efe14d24531444d2fffdf
@@ -1125,7 +1125,7 @@ F test/dbpage.test 2e3a50548edea551ef974b8f121f975852de9c5b16cb3284ac4bf2c9f2ed5
 F test/dbpagefault.test ea39de2ca86041a9c6df1135645180a76d0a8da93ac159e2fafe38e39636530b
 F test/dbstatus.test 4a4221a883025ffd39696b3d1b3910b928fb097d77e671351acb35f3aed42759
 F test/dbstatus2.test a36518c0f0951d8fd5a3dc36f99948ad1af93fb7fc0d2e03e5bb5a643186cf52
-F test/decimal.test ffc6fd5e8617474f023dc6050995002e2975df72eebb449e0379dfd9c8aed74b
+F test/decimal.test 400ac225f1fc5fb068a2ecf8b2834f0a70660a008f385295f48e4349b574bbc6
 F test/default.test a4c9e41318d25e3e6d6adfbb3fbbc198b9c6a3f42b1abd4e24a900dcc6e6b887
 F test/delete.test 2686e1c98d552ef37d79ad55b17b93fe96fad9737786917ce3839767f734c48f
 F test/delete2.test 3a03f2cca1f9a67ec469915cb8babd6485db43fa
@@ -2294,8 +2294,8 @@ F tool/warnings-clang.sh bbf6a1e685e534c92ec2bfba5b1745f34fb6f0bc2a362850723a9ee
 F tool/warnings.sh a554d13f6e5cf3760f041b87939e3d616ec6961859c3245e8ef701d1eafc2ca2
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
 F tool/winmain.c 00c8fb88e365c9017db14c73d3c78af62194d9644feaf60e220ab0f411f3604c
-P e2af533c281989c751fa4a15e8a5ebafa9cad5efadfd37a2407c89e397b3ddf2 606005419f60bd14eec71ee87a770051c8c551273c9a7567d830283eeb1058e8
-R b3c969998688fe748072288abe8a1319
+P 79ba7ba1a75c998c68dd2cc60de7fbe133a563e803a536efea94eff657603965
+R f2d891194425a128a2169bec942eaf9b
 U drh
-Z 34b918f9a0d1d3776adc9d5e49f72fce
+Z ac05c161cd75d9b6c9d4f0aa91c400ab
 # Remove this line to create a well-formed Fossil manifest.
diff --git a/manifest.uuid b/manifest.uuid
index b393032bc4..94c271d5d7 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-79ba7ba1a75c998c68dd2cc60de7fbe133a563e803a536efea94eff657603965
+bf74b51f7e40dd4fbc7bbeba1539a38a0e19252c60ad87d514a09895b47bb506
diff --git a/test/decimal.test b/test/decimal.test
index e65975087f..30da482056 100644
--- a/test/decimal.test
+++ b/test/decimal.test
@@ -272,4 +272,43 @@ do_execsql_test 8210 {
   SELECT quote(decimal_add(x,y)), quote(decimal_sub(x,y)) FROM t2;
 } {'3' '-1' NULL NULL NULL NULL '3.75' '-0.75'}
 
+# Bug 2026-10-19T06:35:26Z (c8ec3b0a1fddd7d2): decimal_cmp() and the
+# decimal collating sequence must ignore leading zeros in the integer
+# part, such as those left behind when an exponent is applied.
+#
+do_execsql_test 8300 {
+  SELECT decimal_cmp('3e-1','0.5'), decimal_cmp('0e1','0.5'),
+         decimal_cmp('0.000001e34','1e28'), decimal_cmp('0e-10','0'),
+         decimal_cmp(decimal('3e-1'), decimal('0.5'));
+} {-1 -1 0 0 -1}
+do_execsql_test 8310 {
+  SELECT decimal_cmp(decimal_exp('0.5'),'0.5'),
+         decimal_cmp('0.5',decimal_exp('0.5'));
+} {0 0}
+do_execsql_test 8320 {
+  SELECT decimal_cmp('-3e-1','-0.5'), decimal_cmp('-0.5','-3e-1'),
+         decimal_cmp('0.04e1','3e-1'), decimal_cmp('000123','1.23e2'),
+         decimal_cmp('12e-1','1.2'), decimal_cmp('12e-1','1.25'),
+         decimal_cmp('0.000001e34','1.0000000000000000000000000001e28');
+} {1 -1 1 0 0 -1 -1}
+do_execsql_test 8330 {
+  CREATE TABLE price(id INTEGER PRIMARY KEY, amount TEXT COLLATE decimal UNIQUE);
+  INSERT INTO price(amount) VALUES('1e28');
+}
+do_catchsql_test 8331 {
+  INSERT INTO price(amount) VALUES('0.000001E+34');
+} {1 {UNIQUE constraint failed: price.amount}}
+do_execsql_test 8332 {
+  INSERT INTO price(amount)
+    VALUES('0.5'),('0e1'),('2'),('0.25'),('3e-1'),('0.04e1'),('1');
+  SELECT group_concat(amount, ' ') FROM (SELECT amount FROM price ORDER BY amount);
+} {{0e1 0.25 3e-1 0.04e1 0.5 1 2 1e28}}
+do_execsql_test 8333 {
+  DELETE FROM price WHERE amount <= '0.5';
+  SELECT group_concat(amount, ' ') FROM (SELECT amount FROM price ORDER BY id);
+} {{1e28 2 1}}
+do_execsql_test 8334 {
+  PRAGMA integrity_check;
+} {ok}
+
 finish_test