diff --git a/query.go b/query.go
index 71d1ba9e..d1191c7c 100644
--- a/query.go
+++ b/query.go
@@ -221,15 +221,6 @@ func (rows *Rows) Scan(dest ...interface{}) (err error) {
 			if err != nil {
 				rows.Fatal(scanArgError{col: i, err: err})
 			}
-		} else if s, ok := d.(ScannerV3); ok {
-			val, err := decodeByOID(vr)
-			if err != nil {
-				rows.Fatal(scanArgError{col: i, err: err})
-			}
-			err = s.ScanPgxV3(nil, val)
-			if err != nil {
-				rows.Fatal(scanArgError{col: i, err: err})
-			}
 		} else if s, ok := d.(pgtype.BinaryDecoder); ok && vr.Type().FormatCode == BinaryFormatCode {
 			err = s.DecodeBinary(vr.bytes())
 			if err != nil {
diff --git a/values.go b/values.go
index fc790dfe..80f4ee52 100644
--- a/values.go
+++ b/values.go
@@ -204,10 +204,6 @@ type Encoder interface {
 	FormatCode() int16
 }
 
-type ScannerV3 interface {
-	ScanPgxV3(fieldDescription interface{}, src interface{}) error
-}
-
 // NullFloat32 represents an float4 that may be null. NullFloat32 implements the
 // Scanner and Encoder interfaces so it may be used both as an argument to
 // Query[Row] and a destination for Scan.