Example caption:
JOHN SMITH AKA JOHN R SMITH FKA JOHNNY R SMITH

Desired output:
Alias Type Found: AKA
Alias Caption Found: JOHN R SMITH
Alias Type Found: FKA
Alias Caption Found: JOHNNY R SMITH

void Main()
{
    var caption = "JOHN SMITH AKA JOHN R SMITH FKA JOHNNY R SMITH";
    caption.Split().ParseAliases( (t,c)=>{
        Console.WriteLine ("Alias Type Found: {0}",t);
        Console.WriteLine ("Alias Caption Found: {0}",c);
    });
}

public delegate void AliasRetrievedDelegate(string aliasType, string aliasCaption);

public static class ParserExtensions{
    private static IEnumerable<string> aliasTypes = new[]{"AKA","FKA"};

    public static void ParseAliases(this IEnumerable<string> tokens,
        aliasRetrievedDelegate d,
        int startIdx = 0){
                   // TODO

    }
}

public static class ParserExtensions
{
    private static IEnumerable<string> aliasTypes = new[]{"AKA","FKA"};

    public static void ParseAliases(this IEnumerable<string> tokens,
        Action<string, string> d,
        int startIdx = 0)
    {
        var aliases = tokens.Skip(startIdx)
                            .GroupMatchesWithTrailing(x => aliasTypes.Contains(x));
        foreach(var alias in aliases)
        {
            string aliasType = alias.Item1;
            string aliasName = string.Join(" ", alias.Item2.ToArray());
            d(alias.Type, alias.Name);
        }
    }

private static IEnumerable<Tuple<T, List<T>>> GroupMatchesWithTrailing<T>(
        this IEnumerable<T> source,
        Func<T, bool> predicate)
    {
        var items = source.SkipWhile(x => predicate(x) == false);
        using (IEnumerator<T> iterator = items.GetEnumerator())
        {
            bool hasItems = iterator.MoveNext();
            while(hasItems)
            {
                T match = iterator.Current;
                List<T> trailing = new List<T>();
                hasItems = iterator.MoveNext();
                while(hasItems && predicate(iterator.Current) == false)
                {
                    trailing.Add(iterator.Current);
                    hasItems = iterator.MoveNext();
                }
                yield return Tuple.Create(match, trailing);
            }
        }
    }
}