diff --git a/rules/package_info.bzl b/rules/package_info.bzl
index c79545f..bd32f3e 100644
--- a/rules/package_info.bzl
+++ b/rules/package_info.bzl
@@ -35,6 +35,7 @@
         package_url = ctx.attr.package_url,
         package_version = ctx.attr.package_version,
     )
+
     # Experimental alternate design, using a generic 'data' back to hold things
     generic_provider = ExperimentalMetadataInfo(
         type = "package_info_alt",
@@ -42,8 +43,8 @@
         data = {
             "package_name": ctx.attr.package_name or ctx.build_file_path.rstrip("/BUILD"),
             "package_url": ctx.attr.package_url,
-            "package_version": ctx.attr.package_version
-        }
+            "package_version": ctx.attr.package_version,
+        },
     )
     return [provider, generic_provider]
 
@@ -64,7 +65,12 @@
             doc = "A human readable version string identifying this package." +
                   " This may be used to produce an index of OSS packages used" +
                   " by an applicatation.  It should be a value that" +
-                  " increases over time, rather than a commit hash."
+                  " increases over time, rather than a commit hash.",
+        ),
+        "purl": attr.string(
+            doc = "A pURL conforming to the spec outlined in" +
+                  " https://github.com/package-url/purl-spec This may be used when" +
+                  " generating an SBOM.",
         ),
     },
 )
@@ -75,20 +81,25 @@
         package_name = None,
         package_url = None,
         package_version = None,
+        purl = None,
         **kwargs):
     """Wrapper for package_info rule.
 
     @wraps(_package_info)
 
+    The purl attribute should be a valid pURL, as defined in the
+    [pURL spec](https://github.com/package-url/purl-spec).
+
     Args:
       name: str target name.
       package_name: str A human readable name identifying this package. This
                     may be used to produce an index of OSS packages used by
                     an application.
       package_url: str The canoncial URL this package distribution was retrieved from.
-                       Note that, because of local mirroring, that might not be the 
+                       Note that, because of local mirroring, that might not be the
                        physical URL it was retrieved from.
       package_version: str A human readable name identifying version of this package.
+      purl: str The canonical pURL by which this package is known.
       kwargs: other args. Most are ignored.
     """
     visibility = kwargs.get("visibility") or ["//visibility:public"]
@@ -97,6 +108,7 @@
         package_name = package_name,
         package_url = package_url,
         package_version = package_version,
+        purl = purl,
         applicable_licenses = [],
         visibility = visibility,
         tags = [],
diff --git a/rules/providers.bzl b/rules/providers.bzl
index c9f89e0..b6a352f 100644
--- a/rules/providers.bzl
+++ b/rules/providers.bzl
@@ -55,6 +55,7 @@
         "package_name": "string: Human readable package name",
         "package_url": "string: URL from which this package was downloaded.",
         "package_version": "string: Human readable version string",
+        "purl": "string: package url matching the purl spec (https://github.com/package-url/purl-spec)",
     },
 )