S-Oil (XKRX:010955) Piotroski F-Score: 6 (As of Sep. 21, 2026) — 50% Above Median

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XKRX:010955 S-Oil Corp XKRX:010955
59 GF Score
Price ₩76,400.00
GF Value ₩38,933.78
Valuation Significantly Overvalued
! 7 Warning Signs
View Full Analysis

What is S-Oil Piotroski F-Score?

S-Oil XKRX:010955 +0.39% 59 Piotroski F-Score is 6 as of Sep. 21, 2026, which is 50% above its 10-year median of 4.00. GuruFocus rates XKRX:010955 with a GF Score™ of 59/100 and a GF Value™ of ₩38,933.78 (Significantly Overvalued). The stock has 7 warning signs investors should review. Among 994 Oil & Gas companies, S-Oil ranks better than 75.25% on this metric.

The zones of discrimination were as such:

Good or high score = 7, 8, 9
Bad or low score = 0, 1, 2, 3

S-Oil has an F-score of 7. It is a good or high score, which usually indicates a very healthy situation.

The historical rank and industry rank for S-Oil's Piotroski F-Score or its related term are showing as below:

XKRX:010955' s Piotroski F-Score Range Over the Past 10 Years
Min: 2   Med: 4   Max: 9
Current: 6

During the past 13 years, the highest Piotroski F-Score of S-Oil was 9. The lowest was 2. And the median was 4.

S-Oil  (XKRX:010955) Piotroski F-Score Explanation

The developer of the system is Joseph D. Piotroski is relatively unknown accounting professor who shuns publicity and rarely gives interviews.

He graduated from the University of Illinois with a B.S. in accounting in 1989, received an M.B.A. from Indiana University in 1994. Five years later, in 1999, after earning a Ph.D. in accounting from the University of Michigan, he became an associate professor of accounting at the University of Chicago.

In 2000, he wrote a research paper called "Value Investing: The Use of Historical Financial Statement Information to Separate Winners from Losers" (pdf).

He wanted to see if he can develop a system (using a simple nine-point scoring system) that can increase the returns of a strategy of investing in low price to book (referred to in the paper as high book to market) value companies.

What he found was something that exceeded his most optimistic expectations.

Buying only those companies that scored highest (8 or 9) on his nine-point scale, or F-Score as he called it, over the 20 year period from 1976 to 1996 led to an average out-performance over the market of 13.4%.

Even more impressive were the results of a strategy of investing in the highest F-Score companies (8 or 9) and shorting companies with the lowest F-Score (0 or 1).

Over the same period from 1976 to 1996 (20 years) this strategy led to an average yearly return of 23%, substantially outperforming the average S&P 500 index return of 15.83% over the same period.


S-Oil Piotroski F-Score Related Terms


S-Oil Piotroski F-Score Historical Data

* Premium members only.

The historical data trend for S-Oil's Piotroski F-Score can be seen below:

* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD.
* For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.

S-Oil Piotroski F-Score Chart

S-Oil Annual Data
Trend Dec16 Dec17 Dec18 Dec19 Dec20 Dec21 Dec22 Dec23 Dec24 Dec25
Piotroski F-Score
Get a 7-Day Free Trial Premium Member Only Premium Member Only 9.00 7.00 3.00 3.00 5.00

S-Oil Quarterly Data
Sep21 Dec21 Mar22 Jun22 Sep22 Dec22 Mar23 Jun23 Sep23 Dec23 Mar24 Jun24 Sep24 Dec24 Mar25 Jun25 Sep25 Dec25 Mar26 Jun26
Piotroski F-Score Get a 7-Day Free Trial Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only 3.00 3.00 5.00 7.00 8.00

XKRX:010955 vs MPC, VLO, PSX: Piotroski F-Score Comparison

For the Oil & Gas Refining & Marketing subindustry, S-Oil's Piotroski F-Score, along with its competitors' market caps and Piotroski F-Score data, can be viewed below:

* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.


S-Oil Piotroski F-Score vs Oil & Gas Industry

For the Oil & Gas industry and Energy sector, S-Oil's Piotroski F-Score distribution charts can be found below:

* The bar in red indicates where S-Oil's Piotroski F-Score falls into.


XKRX:010955
59GF Score
S-Oil Corp XKRX:010955
Piotroski F-Score is just one metric. See GF Score™, valuation, warning signs, and more.
View Full Analysis

How is the Piotroski F-Score calculated?

* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD.
* For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.

This Year (Jun26) TTM:Last Year (Jun25) TTM:
Net Income was 61914 + 225171 + 719868 + 510843 = ₩1,517,796 Mil.
Cash Flow from Operations was 890672 + 1857589 + -523886 + -43076 = ₩2,181,299 Mil.
Revenue was 8415367 + 8792553 + 8942689 + 11343488 = ₩37,494,097 Mil.
Gross Profit was 402499 + 580621 + 1430850 + 1160190 = ₩3,574,160 Mil.
Average Total Assets from the begining of this year (Jun25)
to the end of this year (Jun26) was
(24574915 + 24988920 + 26792773 + 28862781 + 30242119) / 5 = ₩27092301.6 Mil.
Total Assets at the begining of this year (Jun25) was ₩24,574,915 Mil.
Long-Term Debt & Capital Lease Obligation was ₩5,766,994 Mil.
Total Current Assets was ₩11,497,141 Mil.
Total Current Liabilities was ₩14,109,720 Mil.
Net Income was -208224 + -133405 + -45795 + -67841 = ₩-455,265 Mil.

Revenue was 8840623 + 8917081 + 8990533 + 8048504 = ₩34,796,741 Mil.
Gross Profit was -242127 + 419679 + 155752 + -168607 = ₩164,697 Mil.
Average Total Assets from the begining of last year (Jun24)
to the end of last year (Jun25) was
(21935920 + 22523390 + 24638369 + 24131683 + 24574915) / 5 = ₩23560855.4 Mil.
Total Assets at the begining of last year (Jun24) was ₩21,935,920 Mil.
Long-Term Debt & Capital Lease Obligation was ₩4,845,228 Mil.
Total Current Assets was ₩8,583,352 Mil.
Total Current Liabilities was ₩11,029,987 Mil.

*Note: If the latest quarterly/semi-annual/annual total assets data is 0, then we will use previous quarterly/semi-annual/annual data for all the items in the balance sheet.

Profitability

Question 1. Return on Assets (ROA)

Net income before extraordinary items for the year divided by Total Assets at the beginning of the year.

Score 1 if positive, 0 if negative.

S-Oil's current Net Income (TTM) was 1,517,796. ==> Positive ==> Score 1.

Question 2. Cash Flow Return on Assets (CFROA)

Net cash flow from operating activities (operating cash flow) divided by Total Assets at the beginning of the year.

Score 1 if positive, 0 if negative.

S-Oil's current Cash Flow from Operations (TTM) was 2,181,299. ==> Positive ==> Score 1.

Question 3. Change in Return on Assets

Compare this year's return on assets (1) to last year's return on assets.

Score 1 if it's higher, 0 if it's lower.

ROA (This Year)=Net Income/Total Assets (Jun25)
=1517796/24574915
=0.061762

ROA (Last Year)=Net Income/Total Assets (Jun24)
=-455265/21935920
=-0.02075432

S-Oil's return on assets of this year was 0.061762. S-Oil's return on assets of last year was -0.02075432. ==> This year is higher. ==> Score 1.

Question 4. Quality of Earnings (Accrual)

Compare Cash flow return on assets (2) to return on assets (1)

Score 1 if CFROA > ROA, 0 if CFROA <= ROA.

S-Oil's current Net Income (TTM) was 1,517,796. S-Oil's current Cash Flow from Operations (TTM) was 2,181,299. ==> 2,181,299 > 1,517,796 ==> CFROA > ROA ==> Score 1.

Funding

Question 5. Change in Gearing or Leverage

Compare this year's gearing (long-term debt divided by average total assets) to last year's gearing.

Score 0 if this year's gearing is higher, 1 otherwise.

Gearing (This Year: Jun26)=Long-Term Debt & Capital Lease Obligation/Average Total Assets from Jun25 to Jun26
=5766994/27092301.6
=0.21286468

Gearing (Last Year: Jun25)=Long-Term Debt & Capital Lease Obligation/Average Total Assets from Jun24 to Jun25
=4845228/23560855.4
=0.20564737

S-Oil's gearing of this year was 0.21286468. S-Oil's gearing of last year was 0.20564737. ==> Last year is lower than this year ==> Score 0.

Question 6. Change in Working Capital (Liquidity)

Compare this year's current ratio (current assets divided by current liabilities) to last year's current ratio.

Score 1 if this year's current ratio is higher, 0 if it's lower

Current Ratio (This Year: Jun26)=Total Current Assets/Total Current Liabilities
=11497141/14109720
=0.81483835

Current Ratio (Last Year: Jun25)=Total Current Assets/Total Current Liabilities
=8583352/11029987
=0.77818333

S-Oil's current ratio of this year was 0.81483835. S-Oil's current ratio of last year was 0.77818333. ==> This year's current ratio is higher. ==> Score 1.

Question 7. Change in Shares in Issue

Compare the number of shares in issue this year, to the number in issue last year.

Score 0 if there is larger number of shares in issue this year, 1 otherwise.

S-Oil's number of shares in issue this year was 0. S-Oil's number of shares in issue last year was 0. ==> There is smaller number of shares in issue this year, or the same. ==> Score 1.

Efficiency

Question 8. Change in Gross Margin

Compare this year's gross margin (Gross Profit divided by sales) to last year's.

Score 1 if this year's gross margin is higher, 0 if it's lower.

Gross Margin (This Year: TTM)=Gross Profit/Revenue
=3574160/37494097
=0.09532594

Gross Margin (Last Year: TTM)=Gross Profit/Revenue
=164697/34796741
=0.00473312

S-Oil's gross margin of this year was 0.09532594. S-Oil's gross margin of last year was 0.00473312. ==> This year's gross margin is higher. ==> Score 1.

Question 9. Change in asset turnover

Compare this year's asset turnover (total sales for the year divided by total assets at the beginning of the year) to last year's asset turnover ratio.

Score 1 if this year's asset turnover ratio is higher, 0 if it's lower

Asset Turnover (This Year)=Revenue/Total Assets at the Beginning of This Year (Jun25)
=37494097/24574915
=1.52570607

Asset Turnover (Last Year)=Revenue/Total Assets at the Beginning of Last Year (Jun24)
=34796741/21935920
=1.58629048

S-Oil's asset turnover of this year was 1.52570607. S-Oil's asset turnover of last year was 1.58629048. ==> Last year's asset turnover is higher ==> Score 0.

Evaluation

Piotroski F-Score= Que. 1+ Que. 2+ Que. 3+Que. 4+Que. 5+Que. 6+Que. 7+Que. 8+Que. 9
=1+1+1+1+0+1+1+1+0
=7

Good or high score = 7, 8, 9
Bad or low score = 0, 1, 2, 3

S-Oil has an F-score of 7. It is a good or high score, which usually indicates a very healthy situation.

Frequently Asked Questions Learn more about Piotroski F-Score →
What does a Piotroski F-Score of 6 mean?
S-Oil (XKRX:010955) has a Piotroski F-Score of 6 as of Sep. 21, 2026. The Piotroski F-score grades a company's business operating strength from 0-9. View historical data on S-Oil and its competitors. This is 50% above median its historical median of 4.00. Over the past decade, S-Oil's Piotroski F-Score has ranged from 2.00 to 9.00. According to the industry distribution chart, S-Oil ranks #246 out of 994 companies in the Oil & Gas industry, placing it in the top 24.7%.
Is S-Oil's Piotroski F-Score too high?
S-Oil's current Piotroski F-Score of 6 is 50% above median its 10-year median of 4.00. Over the past 10 years, this metric has ranged from a low of 2.00 to a high of 9.00. The Oil & Gas industry median Piotroski F-Score is 5.00. S-Oil's value of 6 is 20% above this industry median. Based on the distribution chart, S-Oil ranks #246 out of 994 companies in the Oil & Gas industry, which is in the top quartile — a strong position relative to peers. Overall, S-Oil has a GF Score™ of 59/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does S-Oil's Piotroski F-Score compare to MPC and VLO?
According to the Oil & Gas industry distribution chart, S-Oil ranks #246 out of 994 companies for Piotroski F-Score. This places S-Oil in the top 25% of its industry — outperforming the majority of peers. The industry median Piotroski F-Score is 5.00. S-Oil's value of 6 is 20% above this benchmark. Historically, S-Oil's own Piotroski F-Score has ranged from 2.00 to 9.00 over the past decade. While the company's 10-year median is 4.00 vs. the industry median of 5.00, S-Oil has consistently been above the industry average. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Piotroski F-Score for an Oil & Gas company?
The median Piotroski F-Score among Oil & Gas companies is 5.00, based on 994 companies in the industry. Companies in the top quartile (top 25%) have a Piotroski F-Score significantly above this median, while those in the bottom quartile fall well below. However, Piotroski F-Score should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. S-Oil's current Piotroski F-Score of 6 is 20% above the industry median. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Piotroski F-Score mean?
A high Piotroski F-Score can signal that a stock is expensive relative to its fundamentals. The Piotroski F-score grades a company's business operating strength from 0-9. View historical data on S-Oil and its competitors. For the Oil & Gas industry, the median Piotroski F-Score is 5.00 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. S-Oil's current Piotroski F-Score is 6, which is 50% above median its own 10-year median of 4.00. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is S-Oil stock overvalued right now?
Based on GuruFocus' analysis, S-Oil (XKRX:010955) is currently considered Significantly Overvalued. The stock's GF Value™ is ₩38,933.78, compared to a current price of ₩76,400.00 — trading 96.2% above its estimated fair value. The current Piotroski F-Score is 6, which is 50% above median its 10-year median of 4.00 and 20% above the Oil & Gas industry median of 5.00. S-Oil's overall GF Score™ is 59/100 with 7 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Piotroski F-Score calculated?
Piotroski F-Score is calculated from a company's financial statements. For S-Oil (XKRX:010955), the current Piotroski F-Score is 6 as of Sep. 21, 2026. GuruFocus calculates this using data sourced from SEC filings and annual reports. See the calculation section and 30-year financial data on this page for the full breakdown.

Is S-Oil (XKRX:010955) Overvalued in 2026?

Based on GuruFocus' analysis, S-Oil stock appears to be overvalued. The current stock price of ₩76,400.00 is trading 96.2% above its estimated GF Value™ of ₩38,933.78. GuruFocus considers S-Oil to be Significantly Overvalued.

Key valuation signals for XKRX:010955:

  • Piotroski F-Score: 6 (50% above median its 10-year median of 4.00)
  • GF Value™: ₩38,933.78 vs. price of ₩76,400.00 (96.2% above fair value)
  • GF Score™: 59/100 with 7 warning signs
  • Industry Position: 20% above the Oil & Gas median (#246 of 994)

No single metric tells the full story. See the XKRX:010955 stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.


S-Oil Business Description

Industry EnergyOil & Gas
Other Exchanges 010950:Korea
Address 192, Baekbeom-ro, Mapo-gu, Seoul, KOR, 04196
S-Oil is an integrated energy company that operates a refinery, petrochemical, and lube oil business. Revenue is primarily derived from refining operations, with the majority of sales from Asian countries. Refining operations include a cracking center, which is used for replacement and low sulfurization of all products that actively respond to changes in market conditions. The company exports ultra-low-sulfur diesel fuel, processed to meet environmental regulations around the world. Other products from S-Oil facilities include LPG, naphtha, kerosene/diesel, B-C oil, and other crude oil byproducts.
59GF Score

Get the complete analysis for XKRX:010955

Piotroski F-Score is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.

₩76,400.00
Price
₩38,933.78
GF Value