diff --git a/apps/flipcash/app/proguard-rules.pro b/apps/flipcash/app/proguard-rules.pro
index c9ac58d40..a97a0d11a 100644
--- a/apps/flipcash/app/proguard-rules.pro
+++ b/apps/flipcash/app/proguard-rules.pro
@@ -7,15 +7,13 @@
 -keepnames class com.flipcash.app.core.AppRoute
 -keepnames class com.flipcash.app.core.AppRoute$**
 
-# Protobuf — keep all generated message classes and their builders.
-# Using type-hierarchy rules so new packages / updated gRPC stubs are
-# caught automatically instead of listing every gen package.
--keep class * extends com.google.protobuf.GeneratedMessageLite { *; }
--keep class * extends com.google.protobuf.GeneratedMessageLite$Builder { *; }
+# Protobuf keep rules ship with the contract packages themselves, from 0.3.0 on:
+# com.flipcash:{ocp,flipcash2}-client-protocol carry them in META-INF/proguard/, which
+# R8 reads straight out of the jar. Downgrading either pin below 0.3.0 silently removes
+# the app's only protobuf keep rule.
 
-# gRPC — keep generated service stubs (abstract + concrete)
+# gRPC — keep the generated client stubs
 -keep class * extends io.grpc.stub.AbstractStub { *; }
--keep class * implements io.grpc.BindableService { *; }
 
 # Keep our scan classes that interact with native. The scanner's JNI constructs
 # these from C++ by name (FindClass("com/kik/scan/UsernameKikCode"), GetMethodID
diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 31ef5f56f..c7d8c5155 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -66,8 +66,10 @@ protovalidate-kt = "0.1.1"
 # Generated client SDKs for the two backend contracts. Separate versions on purpose: the
 # protos are independent (flipcash2 does not import ocp), so the packages move on their own
 # cadence and there is nothing to keep aligned.
-ocp-client-protocol = "0.2.0"
-flipcash2-client-protocol = "0.2.0"
+# 0.3.0 is the first release of either package to ship R8 keep rules for its generated
+# messages, which is what lets proguard-rules.pro drop its own.
+ocp-client-protocol = "0.3.0"
+flipcash2-client-protocol = "0.3.0"
 
 # The Android port is the ONLY libphonenumber this app depends on, deliberately. Google's
 # `com.googlecode` artifact used to sit alongside it; the two ship separate copies of the metadata,