diff --git a/internal/msgfmt/format.go b/internal/msgfmt/format.go
index 79fe5ae..21023e5 100644
--- a/internal/msgfmt/format.go
+++ b/internal/msgfmt/format.go
@@ -141,17 +141,11 @@
 		return b
 
 	case "Timestamp":
-		const minTimestamp = -62135596800  // Seconds between 1970-01-01T00:00:00Z and 0001-01-01T00:00:00Z, inclusive
-		const maxTimestamp = +253402300799 // Seconds between 1970-01-01T00:00:00Z and 9999-12-31T23:59:59Z, inclusive
 		secs := m.Get(fds.ByName("seconds")).Int()
 		nanos := m.Get(fds.ByName("nanos")).Int()
-		switch {
-		case secs < minTimestamp || secs > maxTimestamp:
-			return nil
-		case nanos < 0 || nanos >= 1e9:
+		if nanos < 0 || nanos >= 1e9 {
 			return nil
 		}
-
 		t := time.Unix(secs, nanos).UTC()
 		x := t.Format("2006-01-02T15:04:05.000000000") // RFC 3339
 		x = strings.TrimSuffix(x, "000")
@@ -160,18 +154,11 @@
 		return append(b, x+"Z"...)
 
 	case "Duration":
-		const absDuration = 315576000000 // 10000yr * 365.25day/yr * 24hr/day * 60min/hr * 60sec/min
 		secs := m.Get(fds.ByName("seconds")).Int()
 		nanos := m.Get(fds.ByName("nanos")).Int()
-		switch {
-		case secs < -absDuration || secs > +absDuration:
-			return nil
-		case nanos <= -1e9 || nanos >= 1e9:
-			return nil
-		case (secs > 0 && nanos < 0) || (secs < 0 && nanos > 0):
+		if nanos <= -1e9 || nanos >= 1e9 || (secs > 0 && nanos < 0) || (secs < 0 && nanos > 0) {
 			return nil
 		}
-
 		x := fmt.Sprintf("%d.%09d", secs, int64(math.Abs(float64(nanos))))
 		x = strings.TrimSuffix(x, "000")
 		x = strings.TrimSuffix(x, "000")