using System;
using System.Text.RegularExpressions;
using System.Linq;
 
public class Test
{
	public static void Main()
	{
		string pattern = @"(?<=^(?:[^$]*\$){0,3})[^$]*\$?|[^$](?=\$|$)";
        string[] strings = { 
            "Text1",
            "Text1$Text2$Text3",
            "Text1$Text2$Text3$Text4$Text5$Text6"
        };            
 
        Regex regex = new Regex(pattern);
 
        foreach (String s in strings) {
            Console.WriteLine(string.Join("", from Match match in regex.Matches(s) select match.Value));
        }
	}
}

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