diff --git a/java/base.go b/java/base.go
index 717c727..0d824cb 100644
--- a/java/base.go
+++ b/java/base.go
@@ -645,6 +645,14 @@
 	return j.SdkVersion(ctx)
 }
 
+func (j *Module) MinApiLevelForSdkSnapshot(ctx android.EarlyModuleContext) android.ApiLevel {
+	if j.deviceProperties.Min_sdk_version != nil {
+		return android.SdkSpecFrom(ctx, *j.deviceProperties.Min_sdk_version).ApiLevel
+	} else {
+		return android.NoneApiLevel
+	}
+}
+
 func (j *Module) MaxSdkVersion(ctx android.EarlyModuleContext) android.SdkSpec {
 	maxSdkVersion := proptools.StringDefault(j.deviceProperties.Max_sdk_version, "")
 	// SdkSpecFrom returns SdkSpecPrivate for this, which may be confusing.
diff --git a/java/bootclasspath_fragment.go b/java/bootclasspath_fragment.go
index b6b179c..85c17d3 100644
--- a/java/bootclasspath_fragment.go
+++ b/java/bootclasspath_fragment.go
@@ -769,7 +769,7 @@
 	//  their own.
 	if output.SignaturePatternsPath == nil {
 		output.SignaturePatternsPath = buildRuleSignaturePatternsFile(
-			ctx, output.AllFlagsPath, []string{"*"}, nil, nil)
+			ctx, output.AllFlagsPath, []string{"*"}, nil, nil, "")
 	}
 
 	// Initialize a HiddenAPIInfo structure.
@@ -853,12 +853,10 @@
 	return false
 }
 
-// produceHiddenAPIOutput produces the hidden API all-flags.csv file (and supporting files)
-// for the fragment as well as encoding the flags in the boot dex jars.
-func (b *BootclasspathFragmentModule) produceHiddenAPIOutput(ctx android.ModuleContext, contents []android.Module, input HiddenAPIFlagInput) *HiddenAPIOutput {
+func (b *BootclasspathFragmentModule) generateHiddenApiFlagRules(ctx android.ModuleContext, contents []android.Module, input HiddenAPIFlagInput, bootDexInfoByModule bootDexInfoByModule, suffix string) HiddenAPIFlagOutput {
 	// Generate the rules to create the hidden API flags and update the supplied hiddenAPIInfo with the
 	// paths to the created files.
-	output := hiddenAPIRulesForBootclasspathFragment(ctx, contents, input)
+	flagOutput := hiddenAPIFlagRulesForBootclasspathFragment(ctx, bootDexInfoByModule, contents, input, suffix)
 
 	// If the module specifies split_packages or package_prefixes then use those to generate the
 	// signature patterns.
@@ -866,8 +864,8 @@
 	packagePrefixes := b.sourceOnlyProperties.Hidden_api.Package_prefixes
 	singlePackages := b.sourceOnlyProperties.Hidden_api.Single_packages
 	if splitPackages != nil || packagePrefixes != nil || singlePackages != nil {
-		output.SignaturePatternsPath = buildRuleSignaturePatternsFile(
-			ctx, output.AllFlagsPath, splitPackages, packagePrefixes, singlePackages)
+		flagOutput.SignaturePatternsPath = buildRuleSignaturePatternsFile(
+			ctx, flagOutput.AllFlagsPath, splitPackages, packagePrefixes, singlePackages, suffix)
 	} else if !b.isTestFragment() {
 		ctx.ModuleErrorf(`Must specify at least one of the split_packages, package_prefixes and single_packages properties
   If this is a new bootclasspath_fragment or you are unsure what to do add the
@@ -879,6 +877,49 @@
   should specify here. If you are happy with its suggestions then you can add
   the --fix option and it will fix them for you.`, b.BaseModuleName())
 	}
+	return flagOutput
+}
+
+// produceHiddenAPIOutput produces the hidden API all-flags.csv file (and supporting files)
+// for the fragment as well as encoding the flags in the boot dex jars.
+func (b *BootclasspathFragmentModule) produceHiddenAPIOutput(ctx android.ModuleContext, contents []android.Module, input HiddenAPIFlagInput) *HiddenAPIOutput {
+	// Gather information about the boot dex files for the boot libraries provided by this fragment.
+	bootDexInfoByModule := extractBootDexInfoFromModules(ctx, contents)
+
+	flagOutput := b.generateHiddenApiFlagRules(ctx, contents, input, bootDexInfoByModule, "")
+
+	encodedBootDexFilesByModule := hiddenAPIEncodeRulesForBootclasspathFragment(ctx, bootDexInfoByModule, flagOutput.AllFlagsPath)
+
+	output := &HiddenAPIOutput{
+		HiddenAPIFlagOutput:         flagOutput,
+		EncodedBootDexFilesByModule: encodedBootDexFilesByModule,
+	}
+
+	config := ctx.Config()
+	targetApiLevel := android.ApiLevelOrPanic(ctx,
+		config.GetenvWithDefault("SOONG_SDK_SNAPSHOT_TARGET_BUILD_RELEASE", "current"))
+
+	filterContents := []android.Module{}
+	for _, module := range contents {
+		minApiLevel := android.MinApiLevelForSdkSnapshot(ctx, module)
+		if minApiLevel.GreaterThan(targetApiLevel) {
+			delete(bootDexInfoByModule, module.Name())
+			delete(input.StubDexJarsByScope, module.Name())
+			continue
+		}
+
+		filterContents = append(filterContents, module)
+	}
+
+	if len(filterContents) != len(contents) {
+		flagOutput = b.generateHiddenApiFlagRules(ctx, filterContents, input, bootDexInfoByModule, "-for-sdk-snapshot")
+	}
+
+	// Copy the information and make it available for sdk snapshot.
+	ctx.SetProvider(HiddenAPIInfoForSdkProvider, HiddenAPIInfoForSdk{
+		FlagFilesByCategory: input.FlagFilesByCategory,
+		HiddenAPIFlagOutput: flagOutput,
+	})
 
 	return output
 }
@@ -1044,7 +1085,7 @@
 
 	// Get the hidden API information from the module.
 	mctx := ctx.SdkModuleContext()
-	hiddenAPIInfo := mctx.OtherModuleProvider(module, HiddenAPIInfoProvider).(HiddenAPIInfo)
+	hiddenAPIInfo := mctx.OtherModuleProvider(module, HiddenAPIInfoForSdkProvider).(HiddenAPIInfoForSdk)
 	b.Flag_files_by_category = hiddenAPIInfo.FlagFilesByCategory
 
 	// Copy all the generated file paths.
@@ -1223,6 +1264,15 @@
 	output.FilteredStubFlagsPath = pathForOptionalSrc(module.prebuiltProperties.Hidden_api.Filtered_stub_flags, output.StubFlagsPath)
 	output.FilteredFlagsPath = pathForOptionalSrc(module.prebuiltProperties.Hidden_api.Filtered_flags, output.AllFlagsPath)
 
+	// If the prebuilts module does not provide a signature patterns file then generate one from the
+	// flags.
+	// TODO(b/192868581): Remove once the prebuilts all provide a signature patterns file of their
+	//  own.
+	if output.SignaturePatternsPath == nil {
+		output.SignaturePatternsPath = buildRuleSignaturePatternsFile(
+			ctx, output.AllFlagsPath, []string{"*"}, nil, nil, "")
+	}
+
 	return &output
 }
 
diff --git a/java/hiddenapi_modular.go b/java/hiddenapi_modular.go
index c90b2ff..b0c79c5 100644
--- a/java/hiddenapi_modular.go
+++ b/java/hiddenapi_modular.go
@@ -571,6 +571,23 @@
 
 var HiddenAPIInfoProvider = blueprint.NewProvider(HiddenAPIInfo{})
 
+// HiddenAPIInfoForSdk contains information provided by the hidden API processing for use
+// by the sdk snapshot.
+//
+// That includes paths resolved from HiddenAPIFlagFileProperties and also generated by hidden API
+// processing.
+type HiddenAPIInfoForSdk struct {
+	// FlagFilesByCategory maps from the flag file category to the paths containing information for
+	// that category.
+	FlagFilesByCategory FlagFilesByCategory
+
+	// The output from the hidden API processing needs to be made available to other modules.
+	HiddenAPIFlagOutput
+}
+
+// Provides hidden API info for the sdk snapshot.
+var HiddenAPIInfoForSdkProvider = blueprint.NewProvider(HiddenAPIInfoForSdk{})
+
 // ModuleStubDexJars contains the stub dex jars provided by a single module.
 //
 // It maps a *HiddenAPIScope to the path to stub dex jars appropriate for that scope. See
@@ -953,8 +970,11 @@
 // patterns that will select a subset of the monolithic flags.
 func buildRuleSignaturePatternsFile(
 	ctx android.ModuleContext, flagsPath android.Path,
-	splitPackages []string, packagePrefixes []string, singlePackages []string) android.Path {
-	patternsFile := android.PathForModuleOut(ctx, "modular-hiddenapi", "signature-patterns.csv")
+	splitPackages []string, packagePrefixes []string, singlePackages []string,
+	suffix string) android.Path {
+	hiddenApiSubDir := "modular-hiddenapi" + suffix
+
+	patternsFile := android.PathForModuleOut(ctx, hiddenApiSubDir, "signature-patterns.csv")
 	// Create a rule to validate the output from the following rule.
 	rule := android.NewRuleBuilder(pctx, ctx)
 
@@ -971,7 +991,7 @@
 		FlagForEachArg("--package-prefix ", packagePrefixes).
 		FlagForEachArg("--single-package ", singlePackages).
 		FlagWithOutput("--output ", patternsFile)
-	rule.Build("hiddenAPISignaturePatterns", "hidden API signature patterns")
+	rule.Build("hiddenAPISignaturePatterns"+suffix, "hidden API signature patterns"+suffix)
 
 	return patternsFile
 }
@@ -1045,7 +1065,7 @@
 	return validFile
 }
 
-// hiddenAPIRulesForBootclasspathFragment will generate all the flags for a fragment of the
+// hiddenAPIFlagRulesForBootclasspathFragment will generate all the flags for a fragment of the
 // bootclasspath and then encode the flags into the boot dex files.
 //
 // It takes:
@@ -1060,30 +1080,27 @@
 // * index.csv
 // * all-flags.csv
 // * encoded boot dex files
-func hiddenAPIRulesForBootclasspathFragment(ctx android.ModuleContext, contents []android.Module, input HiddenAPIFlagInput) *HiddenAPIOutput {
-	hiddenApiSubDir := "modular-hiddenapi"
-
-	// Gather information about the boot dex files for the boot libraries provided by this fragment.
-	bootDexInfoByModule := extractBootDexInfoFromModules(ctx, contents)
+func hiddenAPIFlagRulesForBootclasspathFragment(ctx android.ModuleContext, bootDexInfoByModule bootDexInfoByModule, contents []android.Module, input HiddenAPIFlagInput, suffix string) HiddenAPIFlagOutput {
+	hiddenApiSubDir := "modular-hiddenapi" + suffix
 
 	// Generate the stub-flags.csv.
 	stubFlagsCSV := android.PathForModuleOut(ctx, hiddenApiSubDir, "stub-flags.csv")
-	buildRuleToGenerateHiddenAPIStubFlagsFile(ctx, "modularHiddenAPIStubFlagsFile", "modular hiddenapi stub flags", stubFlagsCSV, bootDexInfoByModule.bootDexJars(), input, nil)
+	buildRuleToGenerateHiddenAPIStubFlagsFile(ctx, "modularHiddenAPIStubFlagsFile"+suffix, "modular hiddenapi stub flags", stubFlagsCSV, bootDexInfoByModule.bootDexJars(), input, nil)
 
 	// Extract the classes jars from the contents.
 	classesJars := extractClassesJarsFromModules(contents)
 
 	// Generate the set of flags from the annotations in the source code.
 	annotationFlagsCSV := android.PathForModuleOut(ctx, hiddenApiSubDir, "annotation-flags.csv")
-	buildRuleToGenerateAnnotationFlags(ctx, "modular hiddenapi annotation flags", classesJars, stubFlagsCSV, annotationFlagsCSV)
+	buildRuleToGenerateAnnotationFlags(ctx, "modular hiddenapi annotation flags"+suffix, classesJars, stubFlagsCSV, annotationFlagsCSV)
 
 	// Generate the metadata from the annotations in the source code.
 	metadataCSV := android.PathForModuleOut(ctx, hiddenApiSubDir, "metadata.csv")
-	buildRuleToGenerateMetadata(ctx, "modular hiddenapi metadata", classesJars, stubFlagsCSV, metadataCSV)
+	buildRuleToGenerateMetadata(ctx, "modular hiddenapi metadata"+suffix, classesJars, stubFlagsCSV, metadataCSV)
 
 	// Generate the index file from the CSV files in the classes jars.
 	indexCSV := android.PathForModuleOut(ctx, hiddenApiSubDir, "index.csv")
-	buildRuleToGenerateIndex(ctx, "modular hiddenapi index", classesJars, indexCSV)
+	buildRuleToGenerateIndex(ctx, "modular hiddenapi index"+suffix, classesJars, indexCSV)
 
 	// Removed APIs need to be marked and in order to do that the hiddenAPIInfo needs to specify files
 	// containing dex signatures of all the removed APIs. In the monolithic files that is done by
@@ -1091,15 +1108,42 @@
 	// signatures, see the combined-removed-dex module. This does that automatically by using the
 	// *removed.txt files retrieved from the java_sdk_library modules that are specified in the
 	// stub_libs and contents properties of a bootclasspath_fragment.
-	removedDexSignatures := buildRuleToGenerateRemovedDexSignatures(ctx, input.RemovedTxtFiles)
+	removedDexSignatures := buildRuleToGenerateRemovedDexSignatures(ctx, suffix, input.RemovedTxtFiles)
 
 	// Generate the all-flags.csv which are the flags that will, in future, be encoded into the dex
 	// files.
 	allFlagsCSV := android.PathForModuleOut(ctx, hiddenApiSubDir, "all-flags.csv")
-	buildRuleToGenerateHiddenApiFlags(ctx, "modularHiddenApiAllFlags", "modular hiddenapi all flags", allFlagsCSV, stubFlagsCSV, android.Paths{annotationFlagsCSV}, input.FlagFilesByCategory, nil, removedDexSignatures)
+	buildRuleToGenerateHiddenApiFlags(ctx, "modularHiddenApiAllFlags"+suffix, "modular hiddenapi all flags"+suffix, allFlagsCSV, stubFlagsCSV, android.Paths{annotationFlagsCSV}, input.FlagFilesByCategory, nil, removedDexSignatures)
 
+	// Generate the filtered-stub-flags.csv file which contains the filtered stub flags that will be
+	// compared against the monolithic stub flags.
+	filteredStubFlagsCSV := android.PathForModuleOut(ctx, hiddenApiSubDir, "filtered-stub-flags.csv")
+	buildRuleRemoveSignaturesWithImplementationFlags(ctx, "modularHiddenApiFilteredStubFlags"+suffix,
+		"modular hiddenapi filtered stub flags"+suffix, stubFlagsCSV, filteredStubFlagsCSV,
+		HIDDENAPI_STUB_FLAGS_IMPL_FLAGS)
+
+	// Generate the filtered-flags.csv file which contains the filtered flags that will be compared
+	// against the monolithic flags.
+	filteredFlagsCSV := android.PathForModuleOut(ctx, hiddenApiSubDir, "filtered-flags.csv")
+	buildRuleRemoveSignaturesWithImplementationFlags(ctx, "modularHiddenApiFilteredFlags"+suffix,
+		"modular hiddenapi filtered flags"+suffix, allFlagsCSV, filteredFlagsCSV,
+		HIDDENAPI_FLAGS_CSV_IMPL_FLAGS)
+
+	// Store the paths in the info for use by other modules and sdk snapshot generation.
+	return HiddenAPIFlagOutput{
+		AnnotationFlagsPath:   annotationFlagsCSV,
+		MetadataPath:          metadataCSV,
+		IndexPath:             indexCSV,
+		StubFlagsPath:         stubFlagsCSV,
+		AllFlagsPath:          allFlagsCSV,
+		FilteredStubFlagsPath: filteredStubFlagsCSV,
+		FilteredFlagsPath:     filteredFlagsCSV,
+	}
+}
+
+func hiddenAPIEncodeRulesForBootclasspathFragment(ctx android.ModuleContext, bootDexInfoByModule bootDexInfoByModule, allFlagsCSV android.Path) bootDexJarByModule {
 	// Encode the flags into the boot dex files.
-	encodedBootDexJarsByModule := map[string]android.Path{}
+	encodedBootDexJarsByModule := bootDexJarByModule{}
 	outputDir := android.PathForModuleOut(ctx, "hiddenapi-modular/encoded").OutputPath
 	for _, name := range android.SortedStringKeys(bootDexInfoByModule) {
 		bootDexInfo := bootDexInfoByModule[name]
@@ -1107,43 +1151,15 @@
 		encodedDex := hiddenAPIEncodeDex(ctx, unencodedDex, allFlagsCSV, bootDexInfo.uncompressDex, bootDexInfo.minSdkVersion, outputDir)
 		encodedBootDexJarsByModule[name] = encodedDex
 	}
-
-	// Generate the filtered-stub-flags.csv file which contains the filtered stub flags that will be
-	// compared against the monolithic stub flags.
-	filteredStubFlagsCSV := android.PathForModuleOut(ctx, hiddenApiSubDir, "filtered-stub-flags.csv")
-	buildRuleRemoveSignaturesWithImplementationFlags(ctx, "modularHiddenApiFilteredStubFlags",
-		"modular hiddenapi filtered stub flags", stubFlagsCSV, filteredStubFlagsCSV,
-		HIDDENAPI_STUB_FLAGS_IMPL_FLAGS)
-
-	// Generate the filtered-flags.csv file which contains the filtered flags that will be compared
-	// against the monolithic flags.
-	filteredFlagsCSV := android.PathForModuleOut(ctx, hiddenApiSubDir, "filtered-flags.csv")
-	buildRuleRemoveSignaturesWithImplementationFlags(ctx, "modularHiddenApiFilteredFlags",
-		"modular hiddenapi filtered flags", allFlagsCSV, filteredFlagsCSV,
-		HIDDENAPI_FLAGS_CSV_IMPL_FLAGS)
-
-	// Store the paths in the info for use by other modules and sdk snapshot generation.
-	output := HiddenAPIOutput{
-		HiddenAPIFlagOutput: HiddenAPIFlagOutput{
-			AnnotationFlagsPath:   annotationFlagsCSV,
-			MetadataPath:          metadataCSV,
-			IndexPath:             indexCSV,
-			StubFlagsPath:         stubFlagsCSV,
-			AllFlagsPath:          allFlagsCSV,
-			FilteredStubFlagsPath: filteredStubFlagsCSV,
-			FilteredFlagsPath:     filteredFlagsCSV,
-		},
-		EncodedBootDexFilesByModule: encodedBootDexJarsByModule,
-	}
-	return &output
+	return encodedBootDexJarsByModule
 }
 
-func buildRuleToGenerateRemovedDexSignatures(ctx android.ModuleContext, removedTxtFiles android.Paths) android.OptionalPath {
+func buildRuleToGenerateRemovedDexSignatures(ctx android.ModuleContext, suffix string, removedTxtFiles android.Paths) android.OptionalPath {
 	if len(removedTxtFiles) == 0 {
 		return android.OptionalPath{}
 	}
 
-	output := android.PathForModuleOut(ctx, "modular-hiddenapi/removed-dex-signatures.txt")
+	output := android.PathForModuleOut(ctx, "module-hiddenapi"+suffix, "removed-dex-signatures.txt")
 
 	rule := android.NewRuleBuilder(pctx, ctx)
 	rule.Command().
@@ -1151,7 +1167,7 @@
 		Flag("--no-banner").
 		Inputs(removedTxtFiles).
 		FlagWithOutput("--dex-api ", output)
-	rule.Build("modular-hiddenapi-removed-dex-signatures", "modular hiddenapi removed dex signatures")
+	rule.Build("modular-hiddenapi-removed-dex-signatures"+suffix, "modular hiddenapi removed dex signatures"+suffix)
 	return android.OptionalPathForPath(output)
 }