Between January 27, 2017 and February 27, 2017, the Company sold convertible promissory notes to accredited investors for total gross proceeds to the Company of $1,260,000. The notes had a 90-day maturity, paid 8% annual interest and were convertible into the Company’s Series B convertible preferred stock (the “Series B Preferred Stock”) at a conversion price of $10 per share, beginning fifteen days after being notified of the Series B Preferred Stock offering. On March 31, 2017, the $1,260,000 of principal plus $7,324 of accrued interest owed on the convertible promissory notes was converted into 126,700 shares of Series B Preferred Stock (See Note 12 -Stockholders’ Equity).

The Company’s outstanding debt obligations consist of principal remaining related to 8% convertible notes (the IPG Notes) that were issued during 2010. The conversion option on the IPG Notes expired in 2012, and the IPG Notes are no longer convertible into the Company’s stock. The balance on the IPG Notes is as follows:

^[1] Accrued interest is included as a component of accrued expenses on the accompanying condensed consolidated balance sheets.

During the three and nine months ended September 30, 2017, the Company repaid $25,000 and $140,000, respectively, of principal related to the IPG Notes.

The Company accrued interest expense of $9,463 and $27,863, respectively, during the three and nine months ended September 30, 2017, and $8,294 and $24,457, respectively, during the three and nine months ended September 30, 2016, in connection with the IPG Notes.