diff --git a/libfic/flag_key.go b/libfic/flag_key.go
index c31c8ac7..065cb89f 100644
--- a/libfic/flag_key.go
+++ b/libfic/flag_key.go
@@ -73,7 +73,10 @@ func getHashedFlag(raw_value []byte) [blake2b.Size]byte {
 	return hash
 }
 
-func ExecValidatorRegexp(vre string, val []byte) ([]byte, error) {
+func ExecValidatorRegexp(vre string, val []byte, ignorecase bool) ([]byte, error) {
+	if (ignorecase) {
+		vre = "(?i)" + vre
+	}
 	if re, err := regexp.Compile(vre); err != nil {
 		return val, err
 	} else if res := re.FindSubmatch(val); res == nil {
@@ -92,7 +95,7 @@ func (e Exercice) AddRawFlagKey(name string, help string, ignorecase bool, valid
 	// Check that raw value passes through the regexp
 	if validator_regexp != nil {
 		var err error
-		if raw_value, err = ExecValidatorRegexp(*validator_regexp, raw_value); err != nil {
+		if raw_value, err = ExecValidatorRegexp(*validator_regexp, raw_value, ignorecase); err != nil {
 			return FlagKey{}, err
 		}
 	}
@@ -127,7 +130,7 @@ func (k FlagKey) ComputeChecksum(val []byte) (cksum []byte, err error) {
 
 	// Check that raw value passes through the regexp
 	if k.ValidatorRegexp != nil {
-		if val, err = ExecValidatorRegexp(*k.ValidatorRegexp, val); err != nil {
+		if val, err = ExecValidatorRegexp(*k.ValidatorRegexp, val, k.IgnoreCase); err != nil {
 			return
 		}
 	}