sql 2008 remove duplicates from inner join - sql-server-2008

Question

Using SQL 2008 R2. I am trying to find Employees that are Active, but were previously employees in one of our other companies. The following code works; however, I noticed that if the Employee has worked for more than two companies, I get duplicates. Is there another way that I need to write this so that I do not get duplicates? I have tried using the Group By and case with when exist and nothing seems to work.
SAMPLE DATA
╔═════════════╦══════╦══════════╦══════════╦══════════╦══════════╗
║ SSN ║ PRCo ║ Employee ║ FullName ║ HireDate ║ ActiveYN ║
╠═════════════╬══════╬══════════╬══════════╬══════════╬══════════╣
║ 123-45-6789 ║ 17 ║ 456789 ║ John Doe ║ 05/27/13 ║ Y ║
╠═════════════╬══════╬══════════╬══════════╬══════════╬══════════╣
║ 123-45-6789 ║ 23 ║ 456789 ║ John Doe ║ 08/22/11 ║ N ║
╠═════════════╬══════╬══════════╬══════════╬══════════╬══════════╣
║ 123-45-6789 ║ 1 ║ 456789 ║ John Doe ║ 12/03/07 ║ N ║
╠═════════════╬══════╬══════════╬══════════╬══════════╬══════════╣
║ 999-99-9999 ║ 17 ║ 999999 ║ Jane Doe ║ 05/27/13 ║ Y ║
╠═════════════╬══════╬══════════╬══════════╬══════════╬══════════╣
║ 999-99-9999 ║ 23 ║ 999999 ║ Jane Doe ║ 01/26/09 ║ N ║
╚═════════════╩══════╩══════════╩══════════╩══════════╩══════════╝
Using the following code
select distinct p1.SSN, p1.PRCo, p1.Employee, n.FullName, p1.HireDate, p1.ActiveYN,
case when p1.ActiveYN = 'Y' then 'Y'
when p2.ActiveYN = 'Y' then 'Y'
else 'N' end as AnyActiveCo
from PREH as p1
inner join PREH as p2 on p1.SSN=p2.SSN
left outer join PREHFullName as n on p1.PRCo=n.PRCo and p1.Employee=n.Employee
where p1.PRCo<>p2.PRCo
RESULTS; Row 3 & 5 are duplicates and do not have the desired AnyActiveCo result for an employee that was in 3 different companies; however employees with just 2 companies show fine.
╔═════╦═════════════╦══════╦══════════╦══════════╦══════════╦══════════╦═════════════╗
║ Row ║ SSN ║ PRCo ║ Employee ║ FullName ║ HireDate ║ ActiveYN ║ AnyActiveCo ║
╠═════╬═════════════╬══════╬══════════╬══════════╬══════════╬══════════╬═════════════╣
║ 1 ║ 123-45-6789 ║ 17 ║ 456789 ║ John Doe ║ 05/27/13 ║ Y ║ Y ║
╠═════╬═════════════╬══════╬══════════╬══════════╬══════════╬══════════╬═════════════╣
║ 2 ║ 123-45-6789 ║ 23 ║ 456789 ║ John Doe ║ 08/22/11 ║ N ║ Y ║
╠═════╬═════════════╬══════╬══════════╬══════════╬══════════╬══════════╬═════════════╣
║ 3 ║ 123-45-6789 ║ 23 ║ 456789 ║ John Doe ║ 08/22/11 ║ N ║ N ║
╠═════╬═════════════╬══════╬══════════╬══════════╬══════════╬══════════╬═════════════╣
║ 4 ║ 123-45-6789 ║ 1 ║ 456789 ║ John Doe ║ 12/03/07 ║ N ║ Y ║
╠═════╬═════════════╬══════╬══════════╬══════════╬══════════╬══════════╬═════════════╣
║ 5 ║ 123-45-6789 ║ 1 ║ 456789 ║ John Doe ║ 12/03/07 ║ N ║ N ║
╠═════╬═════════════╬══════╬══════════╬══════════╬══════════╬══════════╬═════════════╣
║ 6 ║ 999-99-9999 ║ 17 ║ 999999 ║ Jane Doe ║ 05/27/13 ║ Y ║ Y ║
╠═════╬═════════════╬══════╬══════════╬══════════╬══════════╬══════════╬═════════════╣
║ 7 ║ 999-99-9999 ║ 23 ║ 999999 ║ Jane Doe ║ 01/26/09 ║ N ║ Y ║
╚═════╩═════════════╩══════╩══════════╩══════════╩══════════╩══════════╩═════════════╝