Regular expression for validating names and surnames?

Although this seems like a trivial question, I am quite sure it is not :)

I need to validate names and surnames of people from all over the world. Imagine a huge list of miilions of names and surnames where I need to remove as well as possible any cruft I identify. How can I do that with a regular expression? If it were only English ones I think that this would cut it:

^[a-z -']+$

However, I need to support also these cases:

• other punctuation symbols as they might be used in different countries (no idea which, but maybe you do!)
• different Unicode letter sets (accented letter, greek, japanese, chinese, and so on)
• no numbers or symbols or unnecessary punctuation or runes, etc..
• titles, middle initials, suffixes are not part of this data
• names are already separated by surnames.
• we are prepared to force ultra rare names to be simplified (there's a person named '@' in existence, but it doesn't make sense to allow that character everywhere. Use pragmatism and good sense.)
• note that many countries have laws about names so there are standards to follow

Is there a standard way of validating these fields I can implement to make sure that our website users have a great experience and can actually use their name when registering in the list?

I would be looking for something similar to the many "email address" regexes that you can find on google.

I'll try to give a proper answer myself:

The only punctuations that should be allowed in a name are full stop, apostrophe and hyphen. I haven't seen any other case in the list of corner cases.

Regarding numbers, there's only one case with an 8. I think I can safely disallow that.

Regarding letters, any letter is valid.

I also want to include space.

This would sum up to this regex:

^[\p{L} \.'\-]+$

This presents one problem, i.e. the apostrophe can be used as an attack vector. It should be encoded.

So the validation code should be something like this (untested):

var name = nameParam.Trim();
if (!Regex.IsMatch(name, "^[\p{L} \.\-]+$")) 
    throw new ArgumentException("nameParam");
name = name.Replace("'", "'");  //' does not work in IE

Can anyone think of a reason why a name should not pass this test or a XSS or SQL Injection that could pass?

---

complete tested solution

using System;
using System.Text.RegularExpressions;

namespace test
{
    class MainClass
    {
        public static void Main(string[] args)
        {
            var names = new string[]{"Hello World", 
                "John",
                "João",
                "タロウ",
                "やまだ",
                "山田",
                "先生",
                "мыхаыл",
                "Θεοκλεια",
                "आकाङ्क्षा",
                "علاء الدين",
                "אַבְרָהָם",
                "മലയാളം",
                "상",
                "D'Addario",
                "John-Doe",
                "P.A.M.",
                "' --",
                "<xss>",
                "\""
            };
            foreach (var nameParam in names)
            {
                Console.Write(nameParam+" ");
                var name = nameParam.Trim();
                if (!Regex.IsMatch(name, @"^[\p{L}\p{M}' \.\-]+$"))
                {
                    Console.WriteLine("fail");
                    continue;
                }
                name = name.Replace("'", "&#39;");
                Console.WriteLine(name);
            }
        }
    }
}