diff --git a/android/all_teams.go b/android/all_teams.go
new file mode 100644
index 0000000..d061649
--- /dev/null
+++ b/android/all_teams.go
@@ -0,0 +1,151 @@
+package android
+
+import (
+	"android/soong/android/team_proto"
+	"path/filepath"
+
+	"github.com/google/blueprint/proptools"
+	"google.golang.org/protobuf/encoding/prototext"
+	"google.golang.org/protobuf/proto"
+)
+
+const ownershipDirectory = "ownership"
+const allTeamsFile = "all_teams.pb"
+
+func AllTeamsFactory() Singleton {
+	return &allTeamsSingleton{}
+}
+
+func init() {
+	registerAllTeamBuildComponents(InitRegistrationContext)
+}
+
+func registerAllTeamBuildComponents(ctx RegistrationContext) {
+	ctx.RegisterSingletonType("all_teams", AllTeamsFactory)
+}
+
+// For each module, list the team or the bpFile the module is defined in.
+type moduleTeamInfo struct {
+	teamName string
+	bpFile   string
+}
+
+type allTeamsSingleton struct {
+	// Path where the collected metadata is stored after successful validation.
+	outputPath OutputPath
+
+	// Map of all package modules we visit during GenerateBuildActions
+	packages map[string]packageProperties
+	// Map of all team modules we visit during GenerateBuildActions
+	teams map[string]teamProperties
+	// Keeps track of team information or bp file for each module we visit.
+	teams_for_mods map[string]moduleTeamInfo
+}
+
+// See if there is a package module for the given bpFilePath with a team defined, if so return the team.
+// If not ascend up to the parent directory and do the same.
+func (this *allTeamsSingleton) lookupDefaultTeam(bpFilePath string) (teamProperties, bool) {
+	// return the Default_team listed in the package if is there.
+	if p, ok := this.packages[bpFilePath]; ok {
+		if t := p.Default_team; t != nil {
+			return this.teams[*p.Default_team], true
+		}
+	}
+	// Strip a directory and go up.
+	// Does android/paths.go basePath,SourcePath help?
+	current, base := filepath.Split(bpFilePath)
+	current = filepath.Clean(current) // removes trailing slash, convert "" -> "."
+	parent, _ := filepath.Split(current)
+	if current == "." {
+		return teamProperties{}, false
+	}
+	return this.lookupDefaultTeam(filepath.Join(parent, base))
+}
+
+// Create a rule to run a tool to collect all the intermediate files
+// which list the team per module into one proto file.
+func (this *allTeamsSingleton) GenerateBuildActions(ctx SingletonContext) {
+	this.packages = make(map[string]packageProperties)
+	this.teams = make(map[string]teamProperties)
+	this.teams_for_mods = make(map[string]moduleTeamInfo)
+
+	ctx.VisitAllModules(func(module Module) {
+		if !module.Enabled() {
+			return
+		}
+
+		bpFile := ctx.BlueprintFile(module)
+
+		// Package Modules and Team Modules are stored in a map so we can look them up by name for
+		// modules without a team.
+		if pack, ok := module.(*packageModule); ok {
+			// Packages don't have names, use the blueprint file as the key. we can't get qualifiedModuleId in this context.
+			pkgKey := bpFile
+			this.packages[pkgKey] = pack.properties
+			return
+		}
+		if team, ok := module.(*teamModule); ok {
+			this.teams[team.Name()] = team.properties
+			return
+		}
+
+		// If a team name is given for a module, store it.
+		// Otherwise store the bpFile so we can do a package walk later.
+		if module.base().Team() != "" {
+			this.teams_for_mods[module.Name()] = moduleTeamInfo{teamName: module.base().Team(), bpFile: bpFile}
+		} else {
+			this.teams_for_mods[module.Name()] = moduleTeamInfo{bpFile: bpFile}
+		}
+	})
+
+	// Visit all modules again and lookup the team name in the package or parent package if the team
+	// isn't assignged at the module level.
+	allTeams := this.lookupTeamForAllModules()
+
+	this.outputPath = PathForOutput(ctx, ownershipDirectory, allTeamsFile)
+	// udc branch diff, use textproto and encode it.
+	data, err := prototext.Marshal(allTeams)
+	if err != nil {
+		ctx.Errorf("Unable to marshal team data. %s", err)
+	}
+
+	WriteFileRuleVerbatim(ctx, this.outputPath, proptools.NinjaEscape(string(data)))
+	ctx.Phony("all_teams", this.outputPath)
+}
+
+func (this *allTeamsSingleton) MakeVars(ctx MakeVarsContext) {
+	ctx.DistForGoal("all_teams", this.outputPath)
+}
+
+// Visit every (non-package, non-team) module and write out a proto containing
+// either the declared team data for that module or the package default team data for that module.
+func (this *allTeamsSingleton) lookupTeamForAllModules() *team_proto.AllTeams {
+	teamsProto := make([]*team_proto.Team, len(this.teams_for_mods))
+	i := 0
+	for moduleName, m := range this.teams_for_mods {
+		teamName := m.teamName
+		var teamProperties teamProperties
+		found := false
+		if teamName != "" {
+			teamProperties, found = this.teams[teamName]
+		} else {
+			teamProperties, found = this.lookupDefaultTeam(m.bpFile)
+		}
+
+		// udc branch diff, only write modules with teams to keep ninja file smaller.
+		if found {
+			trendy_team_id := *teamProperties.Trendy_team_id
+			var files []string
+			teamData := new(team_proto.Team)
+			*teamData = team_proto.Team{
+				TrendyTeamId: proto.String(trendy_team_id),
+				TargetName:   proto.String(moduleName),
+				Path:         proto.String(m.bpFile),
+				File:         files,
+			}
+			teamsProto[i] = teamData
+			i++
+		}
+	}
+	return &team_proto.AllTeams{Teams: teamsProto[:i]}
+}