⁽¹⁾

Late in the fourth quarter of 2018, during an internal review we preliminarily determined that certain of our pricing practices may have resulted in the U.S. Government being overcharged under our General Services Administration ("GSA") Federal Supply Schedule contracts (the "Contracts") (the "GSA Matter"). In fourth quarter 2018, we reduced our total sales by an estimated cumulative adjustment of $4.8 million and recorded imputed interest expense of $0.5 million related to the GSA Matter.

⁽²⁾

During the third quarter of 2018, we performed an analysis of our inventory reserves in connection with our recent new product introductions and acquisitions and recorded a charge of $4.7 million, or approximately 5% of total inventory, increasing our reserve for excess and obsolete inventory based on the determination that quantities on-hand for certain legacy products exceeded our revised sales projections.

Three months ended

(in thousands)

March 31,
2019

June 30,
2019

September 30,
2019

Net income (loss)

$

152

$

(6,405)

$

(6,199)

Interest (income) expense, net

(144)

240

(24)

Income tax expense (benefit)

155

(417)

(182)

Depreciation and amortization

4,749

4,573

4,798

EBITDA

4,912

(2,009)

(1,607)

Loss on foreign currency transactions

195

154

514

Stock-based compensation

2,564

2,752

3,387

GSA sales adjustment ⁽¹⁾

35

5,805

—

Advisory fees for GSA Matter ⁽²⁾

591

653

—

Executive severance costs

—

—

1,217

Executive sign-on bonuses & relocation costs

—

575

270

Present4D impairment ⁽³⁾

—

1,535

—

Adjusted EBITDA

$

8,297

$

9,465

$

3,781

⁽¹⁾

Late in the fourth quarter of 2018, during an internal review we preliminarily determined that certain of our pricing practices may have resulted in the U.S. Government being overcharged under our General Services Administration ("GSA") Federal Supply Schedule contracts (the "Contracts") (the "GSA Matter"). In fourth quarter 2018, we reduced our total sales by an estimated cumulative adjustment of $4.8 million. We also retained outside legal counsel and forensic accountants to conduct a comprehensive review of our pricing and other practices under the Contracts (the "Review"). On July 15, 2019, we submitted a report to the GSA and its Office of Inspector General setting forth the findings of the Review. Based on the results of the Review, in second quarter 2019 we reduced our total sales by an incremental $5.8 million (the "GSA sales adjustment").

⁽²⁾

In connection with the GSA Matter, we retained outside legal counsel and forensic accountants to conduct the Review, which resulted in $1.2 million in advisory fees incurred during the first nine months of 2019.

⁽³⁾

On April 27, 2018, we invested $1.8 million in present4D GmbH ("present4D"), a software solutions provider for professional virtual reality presentations and training environments, in the form of an equity capital contribution. During the second quarter of 2019, we determined it is more likely than not that we will not recover our cost basis in present4D and recorded an impairment charge of $1.5 million, which is included in Other expense, net.