diff --git a/pkg/adaptation/adaptation_suite_test.go b/pkg/adaptation/adaptation_suite_test.go
index 4e3bc639..d77efeec 100644
--- a/pkg/adaptation/adaptation_suite_test.go
+++ b/pkg/adaptation/adaptation_suite_test.go
@@ -201,6 +201,24 @@ var _ = Describe("Plugin connection", func() {
 		s.Cleanup()
 	})
 
+	It("should reject plugins with an invalid name", func() {
+		var (
+			validPlugin = &mockPlugin{
+				name: "abcd-0123+EFGH_4567.ijkl",
+				idx:  "05",
+			}
+			invalidPlugin = &mockPlugin{
+				name: "foo,bar",
+				idx:  "10",
+			}
+		)
+
+		s.Startup()
+
+		Expect(validPlugin.Start(s.dir)).To(Succeed())
+		Expect(invalidPlugin.Start(s.dir)).ToNot(Succeed())
+	})
+
 	It("should configure the plugin", func() {
 		var (
 			plugin = s.plugins[0]
diff --git a/pkg/adaptation/plugin.go b/pkg/adaptation/plugin.go
index 50fbebfe..0441a0c3 100644
--- a/pkg/adaptation/plugin.go
+++ b/pkg/adaptation/plugin.go
@@ -435,9 +435,9 @@ func (p *plugin) qualifiedName() string {
 // RegisterPlugin handles the plugin's registration request.
 func (p *plugin) RegisterPlugin(ctx context.Context, req *RegisterPluginRequest) (*RegisterPluginResponse, error) {
 	if p.isExternal() {
-		if req.PluginName == "" {
-			p.regC <- fmt.Errorf("plugin %q registered with an empty name", p.qualifiedName())
-			return &RegisterPluginResponse{}, errors.New("invalid (empty) plugin name")
+		if err := api.CheckPluginName(req.PluginName); err != nil {
+			p.regC <- fmt.Errorf("plugin registered with an invalid name: %w", err)
+			return &RegisterPluginResponse{}, fmt.Errorf("invalid plugin name: %w", err)
 		}
 		if err := api.CheckPluginIndex(req.PluginIdx); err != nil {
 			p.regC <- fmt.Errorf("plugin %q registered with an invalid index: %w", req.PluginName, err)
diff --git a/pkg/api/owners.go b/pkg/api/owners.go
index 05c1e7c9..86e305e2 100644
--- a/pkg/api/owners.go
+++ b/pkg/api/owners.go
@@ -475,14 +475,7 @@ func (f *FieldOwners) ClaimMount(destination, plugin string) error {
 }
 
 func (f *FieldOwners) ClaimHooks(plugin string) error {
-	plugins := plugin
-
-	if current, ok := f.simpleOwner(Field_OciHooks.Key()); ok {
-		f.clearSimple(Field_OciHooks.Key(), plugin)
-		plugins = current + "," + plugin
-	}
-
-	f.claimSimple(Field_OciHooks.Key(), plugins)
+	f.accumulateSimple(Field_OciHooks.Key(), plugin)
 	return nil
 }
 
@@ -678,6 +671,14 @@ func (f *FieldOwners) ClearRdt(plugin string) {
 	f.clearSimple(Field_RdtEnableMonitoring.Key(), plugin)
 }
 
+func (f *FieldOwners) accumulateSimple(field int32, plugin string) {
+	old, ok := f.simpleOwner(field)
+	if ok {
+		plugin = old + "," + plugin
+	}
+	f.Simple[field] = plugin
+}
+
 func (f *FieldOwners) Conflict(field int32, plugin, other string, qualifiers ...string) error {
 	return fmt.Errorf("plugins %q and %q both tried to set %s",
 		plugin, other, qualify(field, qualifiers...))
diff --git a/pkg/api/owners_test.go b/pkg/api/owners_test.go
index 939274af..4efb53b0 100644
--- a/pkg/api/owners_test.go
+++ b/pkg/api/owners_test.go
@@ -113,3 +113,24 @@ func TestCompoundClaims(t *testing.T) {
 
 	require.Equal(t, api.Field_Annotations.String(), "Annotations", "annotation field name")
 }
+
+func TestAccumulatingOwnership(t *testing.T) {
+	o := api.NewOwningPlugins()
+
+	// claim OCI hooks of ctr0
+	err := o.ClaimHooks("ctr0", "plugin0")
+	require.NoError(t, err, "ctr0 OCI hooks by plugin0")
+
+	// claim OCI hooks of ctr0
+	err = o.ClaimHooks("ctr0", "plugin1")
+	require.NoError(t, err, "ctr0 OCI hooks by plugin1")
+
+	// claim OCI hooks of ctr0
+	err = o.ClaimHooks("ctr0", "plugin2")
+	require.NoError(t, err, "ctr0 OCI hooks by plugin2")
+
+	owners, ok := o.HooksOwner("ctr0")
+	require.True(t, ok, "ctr0 has hooks owners")
+	require.Equal(t, "plugin0,plugin1,plugin2", owners, "ctr0 hooks owners")
+
+}
diff --git a/pkg/api/plugin.go b/pkg/api/plugin.go
index 7eaf8920..e4bfa2e7 100644
--- a/pkg/api/plugin.go
+++ b/pkg/api/plugin.go
@@ -17,6 +17,7 @@
 package api
 
 import (
+	"errors"
 	"fmt"
 	"strings"
 )
@@ -57,3 +58,23 @@ func CheckPluginIndex(idx string) error {
 	}
 	return nil
 }
+
+// CheckPluginName verifies that a plugin name is not empty and only contains
+// characters from the set [a-zA-Z0-9_.+-].
+func CheckPluginName(name string) error {
+	if name == "" {
+		return errors.New("invalid plugin name: name is empty")
+	}
+
+	for _, r := range name {
+		switch {
+		case 'a' <= r && r <= 'z', 'A' <= r && r <= 'Z':
+		case '0' <= r && r <= '9':
+		case r == '-', r == '_', r == '.', r == '+':
+		default:
+			return fmt.Errorf("invalid plugin name %q: contains invalid character %q", name, r)
+		}
+	}
+
+	return nil
+}