diff --git a/pubsublite/internal/wire/publish_batcher_test.go b/pubsublite/internal/wire/publish_batcher_test.go
index 014bd0d6c05..9ace683cd25 100644
--- a/pubsublite/internal/wire/publish_batcher_test.go
+++ b/pubsublite/internal/wire/publish_batcher_test.go
@@ -21,6 +21,7 @@ import (
 	"cloud.google.com/go/internal/testutil"
 	"cloud.google.com/go/pubsublite/internal/test"
 	"github.com/google/go-cmp/cmp"
+	"golang.org/x/xerrors"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
 	"google.golang.org/protobuf/proto"
@@ -187,8 +188,8 @@ func TestPublishBatcherAddMessage(t *testing.T) {
 
 	t.Run("oversized message", func(t *testing.T) {
 		msg := &pb.PubSubMessage{Data: bytes.Repeat([]byte{'0'}, MaxPublishRequestBytes)}
-		if gotErr, wantMsg := batcher.AddMessage(msg, nil), "MaxPublishRequestBytes"; !test.ErrorHasMsg(gotErr, wantMsg) {
-			t.Errorf("AddMessage(%v) got err: %v, want err msg: %q", msg, gotErr, wantMsg)
+		if gotErr := batcher.AddMessage(msg, nil); !xerrors.Is(gotErr, ErrOversizedMessage) {
+			t.Errorf("AddMessage(%v) got err: %v, want err: %q", msg, gotErr, ErrOversizedMessage)
 		}
 	})
 
diff --git a/pubsublite/pscompat/publisher.go b/pubsublite/pscompat/publisher.go
index 06ba362e9a1..8506912d3a1 100644
--- a/pubsublite/pscompat/publisher.go
+++ b/pubsublite/pscompat/publisher.go
@@ -19,9 +19,7 @@ import (
 
 	"cloud.google.com/go/pubsub"
 	"cloud.google.com/go/pubsublite/internal/wire"
-	"golang.org/x/xerrors"
 	"google.golang.org/api/option"
-	"google.golang.org/api/support/bundler"
 
 	ipubsub "cloud.google.com/go/internal/pubsub"
 	pb "google.golang.org/genproto/googleapis/cloud/pubsublite/v1"
@@ -29,31 +27,20 @@ import (
 
 var (
 	// ErrOverflow is set for a PublishResult when publish buffers overflow.
-	ErrOverflow = bundler.ErrOverflow
+	// Use errors.Is for comparing errors.
+	ErrOverflow = wire.ErrOverflow
 
 	// ErrOversizedMessage is set for a PublishResult when a published message
-	// exceeds MaxPublishRequestBytes.
-	ErrOversizedMessage = bundler.ErrOversizedItem
+	// exceeds MaxPublishRequestBytes. Use errors.Is for comparing errors.
+	ErrOversizedMessage = wire.ErrOversizedMessage
 
 	// ErrPublisherStopped is set for a PublishResult when a message cannot be
 	// published because the publisher client has stopped or is in the process of
 	// stopping. PublisherClient.Error() returns the error that caused the
-	// publisher client to terminate (if any).
+	// publisher client to terminate (if any). Use errors.Is for comparing errors.
 	ErrPublisherStopped = wire.ErrServiceStopped
 )
 
-// translateError transforms a subset of errors to what would be returned by the
-// pubsub package.
-func translateError(err error) error {
-	if xerrors.Is(err, wire.ErrOversizedMessage) {
-		return ErrOversizedMessage
-	}
-	if xerrors.Is(err, wire.ErrOverflow) {
-		return ErrOverflow
-	}
-	return err
-}
-
 // PublisherClient is a Pub/Sub Lite client to publish messages to a given
 // topic. A PublisherClient is safe to use from multiple goroutines.
 //
@@ -130,7 +117,6 @@ func (p *PublisherClient) Publish(ctx context.Context, msg *pubsub.Message) *pub
 	}
 
 	p.wirePub.Publish(msgpb, func(metadata *wire.MessageMetadata, err error) {
-		err = translateError(err)
 		if metadata != nil {
 			ipubsub.SetPublishResult(result, metadata.String(), err)
 		} else {
diff --git a/pubsublite/pscompat/publisher_test.go b/pubsublite/pscompat/publisher_test.go
index d794b469b14..4dfe7dfc575 100644
--- a/pubsublite/pscompat/publisher_test.go
+++ b/pubsublite/pscompat/publisher_test.go
@@ -21,8 +21,6 @@ import (
 	"cloud.google.com/go/pubsub"
 	"cloud.google.com/go/pubsublite/internal/test"
 	"cloud.google.com/go/pubsublite/internal/wire"
-	"golang.org/x/xerrors"
-	"google.golang.org/api/support/bundler"
 
 	pb "google.golang.org/genproto/googleapis/cloud/pubsublite/v1"
 )
@@ -176,62 +174,3 @@ func TestPublisherClientTransformMessageError(t *testing.T) {
 		t.Errorf("Publisher.Stopped: got %v, want %v", got, want)
 	}
 }
-
-func TestPublisherClientTranslatePublishResultErrors(t *testing.T) {
-	ctx := context.Background()
-	input := &pubsub.Message{
-		Data:        []byte("data"),
-		OrderingKey: "ordering_key",
-	}
-	wantMsg := &pb.PubSubMessage{
-		Data: []byte("data"),
-		Key:  []byte("ordering_key"),
-	}
-
-	for _, tc := range []struct {
-		desc    string
-		wireErr error
-		wantErr error
-	}{
-		{
-			desc:    "oversized message",
-			wireErr: wire.ErrOversizedMessage,
-			wantErr: bundler.ErrOversizedItem,
-		},
-		{
-			desc:    "oversized message wrapped",
-			wireErr: xerrors.Errorf("placeholder error message: %w", wire.ErrOversizedMessage),
-			wantErr: bundler.ErrOversizedItem,
-		},
-		{
-			desc:    "buffer overflow",
-			wireErr: wire.ErrOverflow,
-			wantErr: bundler.ErrOverflow,
-		},
-		{
-			desc:    "service stopped",
-			wireErr: wire.ErrServiceStopped,
-			wantErr: wire.ErrServiceStopped,
-		},
-	} {
-		t.Run(tc.desc, func(t *testing.T) {
-			verifier := test.NewRPCVerifier(t)
-			verifier.Push(wantMsg, nil, tc.wireErr)
-			defer verifier.Flush()
-
-			pubClient := newTestPublisherClient(verifier, DefaultPublishSettings)
-			result := pubClient.Publish(ctx, input)
-
-			_, gotErr := result.Get(ctx)
-			if !test.ErrorEqual(gotErr, tc.wantErr) {
-				t.Errorf("Publish() got err: (%v), want err: (%v)", gotErr, tc.wantErr)
-			}
-			if !test.ErrorEqual(pubClient.Error(), tc.wireErr) {
-				t.Errorf("PublisherClient.Error() got: (%v), want: (%v)", pubClient.Error(), tc.wireErr)
-			}
-			if got, want := pubClient.wirePub.(*mockWirePublisher).Stopped, false; got != want {
-				t.Errorf("Publisher.Stopped: got %v, want %v", got, want)
-			}
-		})
-	}
-}