diff --git a/services/Directory/FilterLists.Directory.Application/Commands/CreateList.cs b/services/Directory/FilterLists.Directory.Application/Commands/CreateList.cs
index a2cf59608..157d4f688 100644
--- a/services/Directory/FilterLists.Directory.Application/Commands/CreateList.cs
+++ b/services/Directory/FilterLists.Directory.Application/Commands/CreateList.cs
@@ -1,5 +1,9 @@
 using FilterLists.Directory.Domain.Aggregates.FilterLists;
+using FilterLists.Directory.Domain.Aggregates.Languages;
 using FilterLists.Directory.Domain.Aggregates.Licenses;
+using FilterLists.Directory.Domain.Aggregates.Maintainers;
+using FilterLists.Directory.Domain.Aggregates.Syntaxes;
+using FilterLists.Directory.Domain.Aggregates.Tags;
 using FilterLists.Directory.Infrastructure.Persistence.Commands.Context;
 using FluentValidation;
 using MediatR;
@@ -146,10 +150,14 @@ public async Task<Response> Handle(Command request, CancellationToken cancellati
                     .WhereIsDefaultForFilterList()
                     .SingleAsync(cancellationToken);
 
+            // TODO: accept IDs and fetch additional related aggregates
             var filterList = FilterList.CreatePendingApproval(
                 request.Name,
                 request.Description,
                 license,
+                new HashSet<Syntax>(),
+                new HashSet<Language>(),
+                new HashSet<Tag>(),
                 request.ViewUrls.Select(u => (u.SegmentNumber, u.Primariness, u.Url)),
                 request.HomeUrl,
                 request.OnionUrl,
@@ -160,6 +168,13 @@ public async Task<Response> Handle(Command request, CancellationToken cancellati
                 request.ChatUrl,
                 request.EmailAddress,
                 request.DonateUrl,
+                new HashSet<Maintainer>(),
+                new HashSet<FilterList>(),
+                new HashSet<FilterList>(),
+                new HashSet<FilterList>(),
+                new HashSet<FilterList>(),
+                new HashSet<FilterList>(),
+                new HashSet<FilterList>(),
                 request.CreateReason);
             _commandContext.FilterLists.Add(filterList);
 
@@ -167,9 +182,7 @@ public async Task<Response> Handle(Command request, CancellationToken cancellati
 
             return new Response
             {
-                ChangeId =
-                    filterList.Changes.Single()
-                        .Id
+                ChangeId = filterList.Changes.Select(c => c.Id).Single()
             };
         }
     }
diff --git a/services/Directory/FilterLists.Directory.Domain/Aggregates/FilterLists/FilterList.cs b/services/Directory/FilterLists.Directory.Domain/Aggregates/FilterLists/FilterList.cs
index 06c9d0f26..9ae4c96a8 100644
--- a/services/Directory/FilterLists.Directory.Domain/Aggregates/FilterLists/FilterList.cs
+++ b/services/Directory/FilterLists.Directory.Domain/Aggregates/FilterLists/FilterList.cs
@@ -42,6 +42,9 @@ public static FilterList CreatePendingApproval(
         string name,
         string? description,
         License license,
+        IEnumerable<Syntax> syntaxes,
+        IEnumerable<Language> languages,
+        IEnumerable<Tag> tags,
         IEnumerable<(short SegmentNumber, short Primariness, Uri Url)> viewUrls,
         Uri? homeUrl,
         Uri? onionUrl,
@@ -52,21 +55,47 @@ public static FilterList CreatePendingApproval(
         Uri? chatUrl,
         string? emailAddress,
         Uri? donateUrl,
+        IEnumerable<Maintainer> maintainers,
+        IEnumerable<FilterList> upstreamFilterLists,
+        IEnumerable<FilterList> forkFilterLists,
+        IEnumerable<FilterList> includedInFilterLists,
+        IEnumerable<FilterList> includesFilterLists,
+        IEnumerable<FilterList> dependencyFilterLists,
+        IEnumerable<FilterList> dependentFilterLists,
         string? createReason)
     {
-        var urls = viewUrls.Select(u => FilterListViewUrl.Create(u.SegmentNumber, u.Primariness, u.Url))
+        var urls = viewUrls.DistinctBy(u => new { u.SegmentNumber, u.Primariness, u.Url })
+            .Select(u => FilterListViewUrl.Create(u.SegmentNumber, u.Primariness, u.Url))
             .ToList();
         if (urls.Count == 0)
         {
             throw new ArgumentException("At lest one view URL is required.", nameof(viewUrls));
         }
 
-        if (urls.GroupBy(u => new { u.SegmentNumber, u.Primariness })
-            .Any(g => g.Count() > 1))
+        if (urls.GroupBy(u => new { u.SegmentNumber, u.Primariness }).Any(g => g.Count() > 1))
         {
-            throw new ArgumentException(
-                "The segment number and primariness pair must be unique for each view URL.",
-                nameof(viewUrls));
+            throw new ArgumentException("The segment number and primariness pair must be unique for each view URL.", nameof(viewUrls));
+        }
+
+        var upstreamFilterListsSet = new HashSet<FilterList>(upstreamFilterLists);
+        var forkFilterListsSet = new HashSet<FilterList>(forkFilterLists);
+        if (upstreamFilterListsSet.Intersect(forkFilterListsSet).Any())
+        {
+            throw new ArgumentException("A FilterList cannot be both an Upstream and a Fork of the same FilterList.");
+        }
+
+        var includedInFilterListsSet = new HashSet<FilterList>(includedInFilterLists);
+        var includesFilterListSet = new HashSet<FilterList>(includesFilterLists);
+        if (includedInFilterListsSet.Intersect(includesFilterListSet).Any())
+        {
+            throw new ArgumentException("A FilterList cannot be both included in and including of the same FilterList.");
+        }
+
+        var dependencyFilterListSet = new HashSet<FilterList>(dependencyFilterLists);
+        var dependentFilterListSet = new HashSet<FilterList>(dependentFilterLists);
+        if (dependencyFilterListSet.Intersect(dependentFilterListSet).Any())
+        {
+            throw new ArgumentException("A FilterList cannot be both a dependency of and dependent upon the same FilterList.");
         }
 
         var list = new FilterList
@@ -74,6 +103,10 @@ public static FilterList CreatePendingApproval(
             Name = name,
             Description = description,
             License = license,
+            Syntaxes = new HashSet<Syntax>(syntaxes),
+            Languages = new HashSet<Language>(languages),
+            Tags = new HashSet<Tag>(tags),
+            ViewUrls = urls,
             HomeUrl = homeUrl,
             OnionUrl = onionUrl,
             PolicyUrl = policyUrl,
@@ -83,7 +116,13 @@ public static FilterList CreatePendingApproval(
             ChatUrl = chatUrl,
             EmailAddress = emailAddress,
             DonateUrl = donateUrl,
-            ViewUrls = urls,
+            Maintainers = new HashSet<Maintainer>(maintainers),
+            UpstreamFilterLists = upstreamFilterListsSet,
+            ForkFilterLists = forkFilterListsSet,
+            IncludedInFilterLists = includedInFilterListsSet,
+            IncludesFilterLists = includesFilterListSet,
+            DependencyFilterLists = dependencyFilterListSet,
+            DependentFilterLists = dependentFilterListSet,
             IsApproved = false
         };
         list.Changes = new HashSet<FilterListChange>(new[] { FilterListChange.Create(list, createReason) });