Thanks for the comments. I went through the document, is it the 60 days rule you are saying may affect me. I was in UK, never received a curtailment letter (checked with the SAR), that means I have lived lawfully. In my passport I had visa stamped till end of 2015, but when I lost the job, it means ...

Hi
Cam to UK on Tier2 general visa with work permit in 2010 Nov.
Gap in employment for 4 month in 2013 sept to 2014 Jan.
No curtailment letter sent.
Can I apply for ILR now?